Shop
My
Custom
FREE 5-Ingredient Recipe EBook
GET IT NOWMy Zucchini Casserole Recipe Is Like a Cheesy Veggie Gratin
This zucchini casserole is perfect for using up all that summer zucchini you’ve got laying around! Here’s why I make it a lot this time of year:
- Tender summer squash in rich cheese sauce – If you like potatoes au gratin, my zucchini casserole is like a veggie version of those, but with a cheesier, creamier sauce. The combination of melty Swiss, sharp Gruyere, and creamy brie cheeses make it rich and nutty.
- Easy to make – Most of the time to make this dish is hands-off, and it uses simple ingredients you’ll find at any grocery store.
- No soggy or watery texture – A few of you compained about this years ago, so I’ve since improved this recipe to avoid this issue (see my tips below). And it doesn’t require precooking.
- Lighter summer side dish – Yes, it’s a cream sauce, but it also has plenty of vegetables! And unlike many zucchini casserole recipes I’ve seen, mine is gluten-free, without any breadcrumbs or thickeners.
- Uses up a good amount of zucchini – Three to be exact! If you have more than that, try more of my zucchini recipes next, like zucchini fries, zucchini brownies, or zucchini fritters.
I actually struggled with the right name for this dish. Zucchini gratin? Healthy zucchini bake? Best cheesy zucchini casserole ever? Whatever you call it, make this dish with me before summer ends!
“I made this last night and my husband can’t stop eating it! He woke up this morning and said he already had some for breakfast. This was easy to make with ingredients I already had on hand.”
-Lori
Ingredients & Substitutions
Here I explain the best ingredients for my zucchini casserole recipe, what each one does, and substitution options. For measurements, see the recipe card.
- Zucchini – Slice it into rounds. Yellow squash would work equally well. If you want more veggies, make my veggie casserole instead.
- Shredded Cheese – I used a pre-mixed shredded Swiss Gruyere blend for a rich, nutty flavor. You can shred them separately yourself, or use a milder variety, like cheddar or mozzarella cheese. I don’t recommend very hard types, like parmesan cheese, as they don’t get quite as melty.
- Brie Cheese – My creamy thickener without any starch or artificial ingredients. If you want something milder, cream cheese makes an excellent substitute.
- Heavy Cream – Thins out the sauce, but not too much. If you want to use milk, half and half, almond milk, or coconut milk, I recommend using half the amount, so that the dish doesn’t get watery.
- Flavor Boosters – Including butter, minced garlic, Italian seasoning, salt, and pepper. Feel free to swap in individual dried herbs, such as basil or oregano. You can also throw in a pinch of crushed red pepper flakes or chili powder for a kick.
How To Make Zucchini Casserole
I have step-by-step photos here to help you visualize the recipe. For full instructions with amounts and temperatures, see the recipe card.
- Drain the zucchini. Place the zucchini slices in a colander, sprinkle with salt, and drain over the sink for 45 minutes. Doing this prevents a watery casserole! Pat dry.
- Assemble the zucchini casserole. Arrange the slices in rows in a medium baking dish, sprinkling shredded cheese in between. Season with black pepper. (I don’t recommend adding more salt, as we already salted the slices in step 1.)
- Make the sauce. Heat the brie, cream, butter, and garlic in a small saucepan over medium-low heat, stirring often, until melty and smooth. (Alternatively, you can heat the ingredients in a bowl in the microwave and stir every 20-30 seconds.) Add salt to your taste.
- Add the sauce, more cheese, and herbs. Pour the sauce evenly over the zucchini in the baking dish. Sprinkle more shredded cheese on top, followed by Italian seasoning.
- Bake in the preheated oven. Your cheesy zucchini casserole is ready when the squash is tender and the cheese on top is golden brown.
How To Keep Zucchini Casserole From Getting Watery
Zucchini releases a lot of liquid as it bakes, which is why casseroles with it can turn out watery. My best fix is to salt the slices first, let them drain, and pat them dry before layering. It takes extra time, but it’s hands-off, and makes a huge difference.
A few more things that help:
- Use small to medium zucchini. Oversized zucchini have more seeds and moisture, so I find my zucchini casserole turns out more watery with them.
- Patting very dry is important. Draining helps, but don’t forget the paper towel step to remove the surface moisture. Sometimes I need a few layers to get it all.
- You can also precook the zucchini instead of draining: It’s a little more work, but sometimes it’s faster to pop the zucchini slices in the air fryer until tender (I do about 8 minutes at 400 degrees F), instead of waiting for them to release liquid over the sink.
- Use a medium casserole dish, not full size. I used a larger dish from this set, and it’s the perfect size for this zucchini casserole recipe, because it keeps the sauce coating the zucchini instead of spreading too thin. (I use the same one for many of my side dish casseroles, like sweet potato casserole, ratatouille, or broccoli cheese casserole.) If you don’t have that size, the next best would be a 9×9 square casserole dish. For a 9×13, you’d have to scale up the recipe, probably by about 1.5X.
- How to ensure your sauce is smooth: Be careful not to overheat! I use this small saucepan — it heats evenly and is a good size for this amount of sauce. Also, make sure to remove all the rind from the brie, and the cheese needs to melt fully before pouring over the zucchini.
- How to save a watery sauce: This won’t work if you forgot to drain, but if you drained and your zucchini still released too much excess moisture, I’ve had success drying out the sauce by baking for longer. Cover the top of the zucchini casserole, lower the temperature to 350 degrees F, and bake for 10-20 extra minutes, until the sauce thickens.
Zucchini Casserole (Easy & Cheesy)
My cheesy zucchini casserole recipe is like a veggie gratin in rich, creamy cheese sauce. Easy to make with simple ingredients!
Instructions
Tap on the times in the instructions to start a kitchen timer.
-
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 medium casserole dish (I used the larger one in this set), 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 the zucchini casserole for 20-25 minutes, until the cheese on top is dark golden brown and the zucchini is soft.
LAST STEP: Leave a rating to help other readers, or tag me @wholesomeyum on Instagram. I’d love to hear from you!
Maya’s Recipe Notes
Serving size: 1/6 of the entire pan
- Tips: Check out my recipe tips above to help you avoid a watery zucchini casserole, as well as a few of my favorite variations.
- Storage: Keep leftovers in an airtight container in the refrigerator for up to 3-4 days. I don’t recommend freezing, because the sauce texture separates.
- Reheat: This dish is more mushy reheated, but still delicious! You can use the microwave or the oven at 350 degree F.
I provide nutrition facts as a courtesy. Have questions about calculations or why you got a different result? Please see my nutrition policy.
Add Your Notes Your Notes
Try More Of My 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.
Baked Zucchini Casserole Recipe
Recipe Variations
I kept my zucchini casserole simple and cheesy, but it’s easy to change the flavor or turn it into more of a meal:
- Milder sauce – Use cream cheese instead of brie, and mozzarella or cheddar instead of Gruyere. You can also make my yellow squash casserole, which works just as well with zucchini.
- Mix-ins for extra flavor – Sometimes I tuck in sun-dried tomatoes (fresh ones would be too watery), caramelized onions (or simply rings of onion layered with the zucchini), or sauteed mushrooms. Crumbled oven bacon is great on top, too!
- Saute the garlic – I just mixed it with the other sauce ingredients to keep it simple. For more flavor, you can saute it in melted butter before adding the other sauce ingredients.
- Add protein to make it a meal – Feel free to layer diced baked chicken breast, crumbled sausage, or ground beef between the squash layers. Just make sure your protein is precooked. You can also make my chicken zucchini casserole instead.
- Eggs – For a breakfast casserole vibe, whisk 4-6 eggs with the (slightly cooled) cheese sauce before pouring over the squash. This version of the zucchini casserole turns out a bit firmer, since the eggs provide structure.
- Crispy toppings – I don’t usually do this, but some people like panko breadcrumbs on top for a crunchy finish. Just sprinkle them on before baking.
Serving Ideas
This dish pairs well with most proteins! I like it with:
- Chicken – My favorites this time of year are summery options, like pesto chicken, bruschetta chicken, or Greek chicken. But feel free to keep it simple with grilled chicken legs or chicken quarters!
- Beef or Pork – You can’t go wrong with cast iron pork chops or a juicy hanger steak! And while it’s not traditional, I’ve really enjoyed this zucchini casserole as lighter comfort food with my smash burger recipe.
- Seafood – This dish goes so well with pesto salmon or baked halibut. You can even serve it with my seafood boil for a lighter alternative to potatoes.
173 Comments
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!