My
Shop Sugar-Free
Wholesome Yum
Free: Healthy Freezer Meals Recipe Ebook
Get It NowThis post may contain affiliate links, which help keep this content free. (Full disclosure)
This easy, cheesy baked zucchini casserole recipe is perfect for using extra summer produce! Also called zucchini gratin, this dish uses simple ingredients and only takes 10 minutes of hands-on effort. And just like yellow squash casserole, it creates tender slices in a rich, creamy sauce.
The only thing is, I struggled with the name for this dish. Cheesy zucchini gratin? Baked zucchini casserole? Healthy zucchini bake? I couldn’t decide, so I’m using the names interchangeably.
If you still have leftover veggies and get tired of zucchini casserole recipes, try more zucchini recipes next, like zucchini fries, zucchini chips, or zucchini noodle salad.
Why You’ll Love This Zucchini Casserole Recipe
- Summery veggie flavor
- Creamy cheese sauce
- Made with basic ingredients
- 10 minutes to prep
- No panko breadcrumbs or other grains
- Naturally keto-friendly, gluten-free, and low carb side dish
- Loaded with veggies and fiber!
Ingredients & Substitutions
This section explains how to choose the best ingredients for zucchini squash casserole, what each one does in the recipe, and substitution options. For measurements, see the recipe card below.
- Zucchini – Use 3 medium zucchini with firm flesh and no nicks. Yellow squash would work equally well if that’s what you have on hand. Either way, slice the summer squash into thin rounds.
- Salt & Pepper
- Shredded Cheese – I used a pre-mixed shredded Swiss Gruyere blend, but you can also shred Swiss and Gruyere cheese separately yourself and mix them together. Alternatively, any shredded sharp cheese, such as cheddar cheese, will work as well. Harder cheeses, like parmesan cheese, might not melt as smoothly.
- Brie Cheese – Helps the sauce thicken and get creamy. You could also substitute cream cheese instead.
- Heavy Cream – Thins out the sauce, but not too much. I recommend using cream for the thickest sauce possible. Milk, half and half, almond milk, or coconut milk can work, but you’d need to use less so that the dish doesn’t get too watery.
- Butter – Adds richness to the sauce. I use grass-fed butter, but any unsalted variety will work.
- Garlic – Use minced or crushed, fresh or from a jar.
- Italian Seasoning – Use a store-bought mix or make homemade Italian seasoning in minutes.
How To Make Zucchini Casserole
This section shows how to make zucchini gratin, with step-by-step photos and details about the technique, to help you visualize it. For full instructions, including amounts and temperatures, see the recipe card below.
- Drain zucchini. Place the zucchini slices in a colander, sprinkle generously with salt (3/4 teaspoon salt is a good amount), and drain over the sink for 45 minutes. (Doing this prevents a watery casserole!) Pat dry.
- Arrange. Arrange the zucchini slices in rows in a baking dish, sprinkling half of the shredded cheese between each row. Season with pepper. (No salt needed here, as we already salted the slices in step 1.)
- Make sauce. Heat brie, cream, butter, and garlic in a saucepan over medium-low heat. Stir frequently, until cheese melts and sauce is smooth. (Alternatively, you can heat the ingredients in a bowl in the microwave and stir every 20-30 seconds, until melted.) Add salt to taste. Pour the sauce evenly over the zucchini in the baking dish.
- Add more cheese. Sprinkle more shredded cheese on top, followed by Italian seasoning.
- Bake. Place the zucchini casserole in the oven, until the zucchini is soft and the cheese on top is dark golden brown.
Tips For The Best Zucchini Casserole
To make sure your au gratin zucchini turns out perfect, keep these tips in mind.
- Don’t skip the salting and draining step. Otherwise this recipe for zucchini casserole will stay too watery, because the zucchini will release water as it cooks. Salting beforehand removes some of the water in advance.
- Try different cheeses (or herbs). Fresh herbs such as rosemary would also taste delicious with this baked zucchini casserole recipe.
- If sauce stays watery, bake longer. Cover the top of the casserole, lower the temperature to 350 degrees F, and bake for 10-20 minutes more, until the sauce thickens.
- Add a crunchy topping, if desired. Use panko bread crumbs if you want, or crushed pork rinds for a low carb alternative.
Recipe Variations
Looking to elevate your zucchini casserole game? Try these variations for unique flavor and texture:
- Onions – Saute some diced onions (or shallots), and stir them into the cheese sauce mixture, or slice the onion into rings and layer them with the zucchini slices. Caramelized onions would also make an amazing addition.
- Bacon & Cheddar – Mix with 1/2 cup baked bacon (crumbled), 1/4 cup diced red onion, and 3/4 cup grated sharp cheddar cheese. Add a sprinkle of smoked paprika to enhance the flavor.
- Chicken – Add 1 cup of shredded chicken to the casserole mixture before topping with shredded cheese. (Or you can just make this chicken zucchini casserole instead.)
- Pizza – Swap the Swiss Gruyere cheese with mozzarella instead. Spread a layer of marinara sauce over the zucchini with cheese sauce, add your favorite pizza toppings (like pepperoni, sausage, bell peppers, etc.), and top with more shredded mozzarella. Bake as usual.
Storage Instructions
Cover leftovers in an airtight container and store in the refrigerator for up to 3 days.
Can You Freeze Zucchini Casserole?
Avoid freezing this zucchini casserole recipe, as the texture will change too much after thawing.
Reheating Instructions:
Heat in a microwave or 350 degree F oven until warm.
What To Serve With Zucchini Casserole
This dish pairs well with most proteins, but especially Italian dishes! Try these mains:
More Cheesy Veggie Casserole Recipes
If you like a baked zucchini casserole recipe, you’ll enjoy these cheesy favorites too!
Tools To Make Zucchini Gratin
- Colander – A must-have for draining wet vegetables like zucchini.
- Stoneware Dish – The perfect size for this zucchini casserole.
- Small Saucepan – For making the sauce.
Baked Zucchini Casserole Recipe
Zucchini Casserole (Easy & Cheesy!)
This easy zucchini gratin is a baked cheesy zucchini casserole recipe everyone will love! Only 10 minutes prep time & simple ingredients.
Go Ad-FreeRecipe Video
Tap on the image below to watch the video.Like this video? Subscribe to my YouTube cooking channel for healthy recipes weekly! (Click the bell icon to be notified when I post a new video.)
Ingredients
Tap underlined ingredients to see where to get them. Please turn Safari reader mode OFF to view ingredients.
Instructions
Tap on the times in the instructions below to start a kitchen timer while you cook.
-
Toss the zucchini slices with sea salt. Place into a colander and set over the sink to drain for 45 minutes. Pat dry at the end.
-
Preheat the oven to 400 degrees F (204 degrees C).
-
In a small 1.5 quart (1.5 L) casserole dish, arrange the zucchini slices in several overlapping rows, sprinkle lightly with shredded cheese. Add another row and more shredded cheese. Continue alternating zucchini and cheese until you fill the entire baking dish. You’ll use about 3/4 cup (half of the total) cheese altogether. Season lightly with black pepper.
-
Combine the brie, cream, butter, and garlic in a small saucepan. Heat for a few minutes on the stove over low to medium-low heat, stirring frequently, until the cheese melts and the mixture is smooth. If desired, add sea salt to taste. Pour the mixture evenly over the zucchini.
-
Sprinkle the remaining 3/4 cup shredded cheese blend on top. Top with Italian seasoning.
-
Bake for about 20-25 minutes, until the cheese on top is dark golden brown and the zucchini is soft.
Last Step: Leave A Rating!
Share your recipe picture by tagging @wholesomeyum and hashtag it #wholesomeyum on Instagram – I’d love to see it!
Related Easy Recipes
Recipe Notes
Serving size: 1/6 of entire pan
Nutrition facts are provided as a courtesy. Have questions about calculations or why you got a different result? Please see our nutrition policy.
Want to save this recipe?
Create a free account to save your favorite recipes!
Sign Up To Save Recipes© Copyright Maya Krampf for Wholesome Yum. Please DO NOT SCREENSHOT OR COPY/PASTE recipes to social media or websites. We’d LOVE for you to share a link with photo instead. 🙂
123 Comments
Arielle
0I made this for Christmas and it was excellent. I didn’t have brie or heavy cream, so I used some fontina and half & half. I’m looking forward to trying this again with the heavy cream.
Ximena
0Great reciepe!!! It came out delicious eventhough I used zucchini and eggplant.
Rhonda Sherlock
0This is delicious!
Cathy
0I am having to use 10% cream as I don’t have heavy cream. What will it do to the zucchini casserole? Should I modify anything ?
Wholesome Yum M
0Hi Cathy, Your casserole may be a little looser, but the recipe will still work fine without any alterations.
Cathy
0Made this once and it became my go-to recipe for the rest of the zucchini season! Delicious!
Janet Savoy
0I love your recipes..can you recommend recipes that can be prepared in an air fryer.and how to reheat in a microwave?
Wholesome Yum M
0Hi Janet, I have several air fryer recipes, including Keto Onion Rings, Chicken Wings, Stuffed Baby Artichokes, Fried Chicken, and Jicama Fries. All of these recipes can be reheated in the air fryer, oven, or microwave.
Janet Savoy
0Hello..how do you fix a zucchini casserole recipe thts a little too salty?
Wholesome Yum M
0Hi Janet, You can stir in a little extra cooked heavy cream to help with the saltiness.
Joyce
0This recipe was great! I really enjoyed it and a great way to make zucchini! Thanks for sharing!!
Valerie Tafat-Johnson
0Can you do this in an instant pot?
Wholesome Yum M
0Hi Valerie, Sorry, the casserole would be too watery if cooked in an Instant Pot.
Johelen
0This is a great recipe and it’s our dinner tonight. Simple and wholesome. The poor rating is because of the overwhelming saturation of ad content. Way too frustrating to swim through it all to get to the back to the recipe twice.
Maya | Wholesome Yum
0Hi Johelen, I’m glad you liked the recipe. I only accept ratings for my actual recipes, not the website. 🙂 Ads keep the Wholesome Yum website running and allow me to develop recipes that readers like you can access absolutely free. However, you may be interested in Wholesome Yum Plus, which includes an ad-free version of the website, along with other perks.
tonya sanchez
0Can I add a little flour in between my layers like I add to my scallop potatoes, and what effect would it have?
Wholesome Yum M
0Hi Tonya, In traditional scalloped potatoes, adding flour between layers basically holds and thickens the sauce in between each layer while it bakes in the oven. This step is really not necessary in this recipe since you are making a cheese sauce to pour over the zucchini. I hope this helps.
Alpa
0I do view your site, but it goes on and on… I was looking at the zucchini recipe but gave up as it just kept going on and on.
Like you, patience is not my strong point. Cooking for a family of 6 I don’t have time for reading long recipes, a shame, as it looked good. Sorry.
Thanks anyway.
Wholesome Yum M
0Hi Alpa, If you would like to skip the post you can go straight to the recipe by using the ‘Jump to Recipe’ button located under the recipe title on the page. I hope this helps.
Amanda C.
0Three stars because it TASTED great, but was way too watery. I drained zucchini and patted dry as directed and cooked longer than 35 minutes. I’m going to try it again because it was yummy,but without the 2 tbsp of almond milk in hopes that the moisture will cut down.
Dina Kassir
0Hello Maya, I’m having a hard time finding the measurments for different types of Keto Bread and sometimes the recipes. All the videos and commercials on your Blog site are getting in the way. I’m getting a headache. I got your cookbook Wholesome Yum, can’t find a variety of bread recipes in it.
Dina
Wholesome Yum M
0Hi Dina, If you can see the recipe cards, then you may need to turn off your browser’s ‘Reader Mode.’ That should allow you to see the amounts listed in the recipe.
Susan
0This was soooo good! I made the six portion size for three of us!! Two of us are most of it leaving a small portion for the third when he comes in from work! It’s definate make again meal. Served with cauliflower and salad. Yum yum!
Lacey
0What can I substitute for the brie? I’m not a fan of it.
Wholesome Yum M
0Hi Lacey, I suggest using Camembert, it behaves similarly to brie in recipes and delicious!
Cathie Davis
0I am NOT a brie lover …. cannot tolerate it in any form. What cheese can I substitute for brie in this recipe?
Wholesome Yum M
0Hi Cathie, I suggest using Camembert, it behaves similarly to brie in recipes and delicious!
e
0Delicious & easy.
Monet
0I do not have a casserole dish (sad, I know)… would I be able to bake this in a regular pan?
Wholesome Yum M
0Hi Monet, An oven safe bowl would work too. Anything oven safe with high sides to contain the casserole will work fine.
Leslie Metzger
0My husband just loves this dish and he keeps the fridge stocked with the ingredients, BUT I’m not a fan. Although my dish looks like the picture here and has a good taste, I don’t like mushy vegetables.
I’ve made this 7 or 8 times for him (not for me, although I eat it freshly baked – leftovers are all his, as the texture gets worse with reheating). I’ve tried several ideas to cut the mush – let the zucchini drain a little longer, use smaller zucchini (less water), lay them out on a paper towel & pat them dry, omit the milk & increase the cream a little, cut down the baking time – nothing has helped. The best part of this casserole for me is the corners – the browned baked cheese has a
little crunch to offset the very soft zucchini.
Not a winner but I’ll keep baking it for him.
Holly B.
0Can this casserole be frozen? Can we freeze any zucchini casserole?
Wholesome Yum M
0Hi Holly, Yes, this casserole should freeze well. The zucchini will be more delicate once it’s reheated, but it will still taste as good!
Judy
0Hi. Do you think it would be a nice alternative to grate the zuchinni instead of slicing it?
Wholesome Yum
0That sounds wonderful, Judy! Let me know how it goes!
Maria Bermudez
0Can I substitute with yellow squash, I know that probably means more carbs but I have a lot of squash right now haha, thanks
Maya | Wholesome Yum
0Hi Maria, Yes, absolutely! The carb difference is very slight and yellow squash are still definitely low carb.
Jackie Nowak
0I made it today Sooooo good!!!!!! Thank you
Bill
0We made this last night and it was spectacular! Salting the zucchini was a great suggestion and it worked. Simple, quick and superb!
Buffie
0Looks awesome! I’m always looking to add more eggplant to my rotation. Do you think that this will work with eggplant too?
Wholesome Yum
0Hi Buffie, I think that could work! Don’t skip the salting and draining step, since that will help keep it from getting too watery.
Jennifer
0If I want to prepare this the night before and be able to bake it for Easter lunch the next day, can I just stick it in the fridge?
Maya | Wholesome Yum
0Hi Jennifer, You can, but it might get a bit more watery. Another option is to slice the zucchini and make the sauce separately ahead, but assemble the day of.
Trish O’Leary
0This was delicious!!! Would definitely make again. Followed recipe exactly and was very flavorful!
Leah
0This recipe is so delicious! A great way to get some more veggies into my kids too.
Thanks for creating such amazing recipes, can’t wait to try more!
Cookilicious
0Vegetarian casseroles are my go-to when I am in a hurry especially on weeknights! Loved how simple and easy your recipe is.
Amy
0This looks so comforting and delicious, I love it!
Sonal
0In love with the Zucchini au gratin. Loved your tips as well.
Sandi
0What a delicious side dish…it even convinced my kids to try zucchini.
Gloria
0You can NEVER have too many zucchini recipes, especially during the growing season. You will never miss the carbs with all the cheese here. This is such a great dish to take along to a potluck. I know my family loves this too.
Shanika
0I love eating casseroles but never used zucchini before trying this! This was so good! Definitely, need to make this again!
Kate Cordova
0Hi Maya,
What do you think about adding ground beef to make it a main course? Haven’t made it yet, but sounds wonderful.
Kate
Maya | Wholesome Yum
0Hi Kate, Sure, you can definitely do that! Just brown it on the stovetop first.
Breann
0I’m curious if this dish would work well using heavy cream instead of almond milk? I’ve tried zucchini au gratin twice before (it just turns out an oily mess). Wondering if using heavy cream is the reason? But my husband is allergic to almond. Any ideas?
Maya | Wholesome Yum
0Hi Breann, That should work, but you might need a bit more since it’s thicker. I can’t comment on why other recipes might not have turned out, though. I’ve tested this one a couple times and it works at least as written.
Brandon Mercker
0Prep time 10 minutes… first step 45 minutes…
Maya | Wholesome Yum
0Hi Brandon, The prep time refers to active time prepping. The step to drain the zucchini is not hands-on prep time. Hope you’ll get the chance to try the recipe.
Luciana Varverud
0Hi! I baked this recipe ahead of time and then froze it. I forgot to bake it for only half the time and then freeze it. I cooked all the way and then froze it. How should I reheat it? Thanks!
Maya | Wholesome Yum
0Hi Luciana, No problem – you can still just reheat it in the oven. It just tastes slightly more fresh the other way, but will still be fine!
Doreen
0This was delicious!! I had to use goat cheese as I cannot drink cow’s milk or anything made with it, but I still found the recipe really tasty.
Maya | Wholesome Yum
0I am so happy you liked it, Doreen! Thanks for stopping by!
Gerry Clough
0Err low carb? with cheese and heavy cream?
Anyway I try to have no meat for 2 days a week and I had all the ingredients except cream for this recipe.
Just used some 2% milk instead and it tasted great!!
Easy peasy and tasty – big thumbs up!
Maya | Wholesome Yum
0Hi Gerry, Yes, both cheese and heavy cream are very low carb. 🙂 I’m glad you liked the recipe. Keep in mind that 2% milk does have a fair amount of carbs if that matters to you, but otherwise works just fine.
Dee
0We made this creamy cheesy zucchini dish for dinner with steak…it was delicious!!! I used shredded cheese on top
and cream cheese inside!! Only changed it because I didn’t have the other ingredients…
Maya | Wholesome Yum
0I am so happy you liked it, Dee! Thanks for stopping by!
Kimberly
0I made this casserole and it had way too much liquid, was very crunchy, and was not a casserole per se. It had no cheese around the zucchini. Only on top. I followed the instructions to the letter. What did I do wrong?
Maya | Wholesome Yum
0Hi Kimberly, Sorry you had issues with it. It sounds like it definitely needed to be cooked for longer, as the zucchini should not be crunchy. Possible reasons for them being crunchy include slicing the zucchini thicker (it needs to be 1/4-inch thick slices), your oven running a little cool, or simply taking the pan out too soon (the cheese needs to be dark golden brown and zucchini should be soft). Finally, if there was a lot of liquid, the zucchini likely needed to sit over the sink to drain for longer, or you needed to pat dry more to get rid of the moisture. If you sliced yours thicker, that could contribute to this as well. The sauce should be all around the zucchini, but in the original I did only place the cheese on top. I actually love your feedback on that, so I re-tested the recipe today and modified it to include some cheese between the rows as well. Hope it works out better next time!
Sarah
0You mention the draining of the zucchini step at the beginning yet you never mention when you actually do it in the recipe. What the heck?
Maya | Wholesome Yum
0Hi Sarah, The draining step is right on the recipe card in step 1.
Debbie
0I made this for a Memorial Day get together. It was amazing! I had requests for the recipe.
Maya | Wholesome Yum
0Thank you so much, Debbie! I’m glad you liked it.
Kamala Ayyagari
0Could I make it to freeze? And how would I do it?
Maya | Wholesome Yum
0Hi Kamala, You can make the recipe as written and pre-bake for about half the time, then let cool to room temperature and freeze. Later you can bake from frozen until hot and bubbly. The texture may be slightly different than fresh but should still work.
Alison
0I made this under protest as I really don’t like courgettes, but I’m staying with my daughter who orders a veg box each week and it’s the only thing I could find that I thought looked ok to use up her courgettes.
Well I must say it was absolutely delisious and went perfectly with our
roast chicken. Lovely recipe
Maya | Wholesome Yum
0Yay! I am so happy you liked it, Alison!
Jersey Girl
0Amazing recipe. I’m not a fan of zucchini or Italian seasoning, or at least that’s what I thought. Last night I made this recipe for the second time. Delicious. Served it with scallops cooked in butter with a little salt, pepper, smoked paprika and cream in the pan to make a little sauce. Wow! Great recipe if it got me to eat zucchini and like it so much I made it a second time. Thank you, thank you, thank you.
Maya | Wholesome Yum
0I’m so glad you liked it! Zucchini can be delicious!
Kaylee
0Could cream cheese sub the brie?
Maya | Wholesome Yum
0Hi Kaylee, Yes! The flavor would be a little different but still delicious!
Brandy
0Hi I am wondering if all your recipes have the nutritional information? I’m excited to start cooking healthy again. The recipes all look delicious
Maya | Wholesome Yum
0Hi Brandy, Yes, they do! Thank you!