The squash casserole my mom’s farm inspired

If you’ve got summer squash multiplying faster than you can cook it, I know the feeling. My mom has a farm, and every summer she sends me home with bags and BAGS of zucchini and yellow squash.
I’ve turned that haul into just about everything, from Sautéed Zucchini and Squash and Parmesan Crusted Zucchini to a big batch of Crispy Zucchini Fritters. But there’s only so much a family can get through before some of it starts to go.
This Summer Squash Casserole was always one of my favorite summer sides growing up. The classic version is usually loaded with sour cream, mayo, and crushed Ritz crackers.
(Now don’t get me wrong… I LOVE those buttery crackers. Just not on a random Tuesday.)
So I made a lighter one. Just sliced zucchini and yellow squash layered up, salted so they don’t turn watery, and topped with Parmesan and crispy panko breadcrumbs.
A few minutes under the broiler and the top goes golden and crisp. It holds its own next to the heavy version, and it’s the one my family actually asks for again and again!
A friend gave me several zucchini & yellow squash from her garden. I sure didn’t want to let them go to waste since I live alone. Found this recipe online and decided to make it. It did not disappoint. The texture was perfect, the squash slices were tender, but kept their shape and with the crumb in Parmesan cheese topping, it was very tasty. I will make this again.
– Linda


Ingredients and Substitutions
For the exact measurements and detailed instructions, please see the recipe card below.

- Parsley. Not absolutely necessary but it makes the casserole really pretty when serving. You can also use fresh thyme or other herbs you love.
- Squash. Feel free to use all yellow summer squash or all zucchini if that’s what you have. However, the alternating colors are what make this casserole so unique and pretty!
- Olive oil. You can also use any other type of oil that does not have a ton of flavor. Avocado, safflower, and sunflower oils will all work equally as well.
- Garlic Powder. You only need a little bit, but it’s the secret ingredient that gives this dish a unique flavor!
- Parmesan cheese. Regular, dairy-filled Parmesan cheese is best. You can also use vegan and dairy-free Parmesan cheese. If necessary, you can sub in another variety, like sharp cheddar cheese, but the result won’t be quite the same.
- Panko Breadcrumbs. You can use regular breadcrumbs or gluten-free breadcrumbs. The taste will be minimally affected. You can substitute with a seasoned breadcrumb mixture, but you will need to make sure to adjust the amount of salt you add
Step-by-step Instructions
Please see the recipe card below for the full instructions, ingredient amounts, and a printable recipe.
Prep the squash.
Slice the squash into ¼-inch rounds using a mandolin or sharp knife. Thicker slices will need more time; thinner ones can turn soggy.
Sprinkle with salt and let sit for 10 minutes, then pat dry. This draws out excess moisture so the casserole bakes up crisp instead of watery.


Layer in the pan.
Layer the zucchini and yellow squash, alternating types, in a 9-inch square baking dish.


Season the casserole.
Lightly season the layered squash with salt and pepper.
Whisk together breadcrumbs, Parmesan cheese, and garlic powder. Then, pour the mixture in an even layer over the zucchini and squash.

Bake in the oven.
Cover the baking dish with aluminum foil and bake in preheated 350°F oven for 30 minutes. It may take a few minutes more if the slices were cut thick, or less time if the squash slices are thin.
Broil for 3-5 minutes. Keep a close eye on it! The topping will crisp up and turn golden brown quickly.

Ways to change it up
- Italian breadcrumbs: These work too. Just go easy on the added salt, since they’re already seasoned.
- All one squash: Use all zucchini or all yellow squash if that’s what you’ve got. The alternating colors just make it prettier.
- Cheese: Parmesan keeps it light and salty. A little sharp cheddar on top makes it richer if that’s the mood.
- Herbs: Fresh parsley is my go-to, but thyme or basil are both great here.
- Gluten-free: Swap in Aleia’s gluten-free panko and nobody will know the difference.
How to store and reheat squash casserole
- Fridge: Let it cool, then store leftovers in an airtight container for 3 to 4 days.
- Reheating: Pop it back in a 350-degree oven or the air fryer for a few minutes to bring back the crispy top. The microwave works in a hurry, but the topping goes soft.
- Make ahead: Assemble the whole thing, cover, and keep it in the fridge for up to 2 days. Bring it to room temperature and bake right before serving.
- Freezing: I don’t recommend freezing this one. Summer squash holds a lot of water, so it turns soft and watery after it thaws.
FAQs
The answer to keeping your casserole from getting watery is to salt before cooking. Squash releases extra moisture while cooking. However, there is a trick to prevent this. After you’ve sliced your squash, sprinkle it with salt, let it sit for about 10 minutes, then blot dry the moisture that the salt drew out.
Nope, leave the skin on. It’s thin and tender, it adds color, and it helps the slices hold their shape as they bake.
Totally. Use whatever you have, or whatever your garden is overrun with. The mix of colors just makes it prettier on the table.
Yes. Just use gluten-free panko breadcrumbs in place of regular. Everything else in the recipe is already gluten-free.
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Zucchini and Squash Casserole Recipe

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Ingredients
- 2 pounds summer squash zucchini and yellow squash, cut into ¼-inch slices
- 2 ½ tablespoons olive oil
- 1 ¼ teaspoons salt divided
- ½ teaspoon pepper
- ⅓ cup grated Parmesan cheese grated
- ⅓ cup Panko breadcrumbs gluten-free
- ¼ teaspoon garlic powder
- 2 tablespoons fresh parsley finely chopped
Instructions
- Preheat the oven to 350℉.
- Cut yellow squash and zucchini into thin, ¼-inch slices. Sprinkle ½ teaspoon salt over the zucchini and squash slices. Let sit for 10 minutes and then dab to remove excess moisture with a paper towel.2 pounds summer squash

- Spray a 9-inch square baking dish with non-stick cooking spray. Alternatively, overlap the zucchini and squash in a row. You should be able to form 4 rows.* Drizzle olive oil over the zucchini and squash and then sprinkle with salt and pepper.

- In a small bowl combine Parmesan cheese, breadcrumbs, and garlic powder. Toss to combine and then sprinkle over the zucchini and squash.⅓ cup grated Parmesan cheese, ⅓ cup Panko breadcrumbs, ¼ teaspoon garlic powder

- Cover baking dish with aluminum foil and bake in preheated oven for 30 minutes.
- Remove foil and turn heat to a High broil. Broil for an additional 5-7 minutes, or until breadcrumb topping starts to turn a golden brown. Serve immediately with fresh parsley and enjoy!

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Notes
- Cheese: Can use a vegan Parmesan cheese substitute.
- Squash: I like to get small-medium, similarly-sized summer squash so they will be able to fit into four rows easily!
- Tools: A mandolin gives you the most precise slices so they all cook at a similar rate.
- Salt: A little salt will help prevent a soggy mess. Let the salted squash sit, then blot dry. The salt draws out excess moisture.
- Breadcrumbs: Try out Italian breadcrumbs. Since they’re pre-seasoned and often contain salt, you will have to adjust the other seasoning ingredients.
- Broiling: This gives it a great crunchy topping.
- Storage: Store leftovers in an airtight container in the fridge for 3 to 4 days.
- Make ahead: Assemble, cover, and refrigerate for up to 2 days. Bring to room temperature and bake right before serving.
- Freezing: Not recommended. Summer squash holds a lot of water, so it turns soft and watery after thawing.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
What to Serve with Squash Casserole?
This dish is an excellent side for family meals. Try one of these recipes alongside it.
For some flavor, try out this Hot Honey Chicken. Or get fancy with Chicken Cordon Bleu.
Skip the potatoes and try this zucchini casserole with Air Fryer Steak or Filet Mignon.
If you’re a seafood lover, go for Panko Crusted Salmon, Lemon Garlic Baked Salmon or Air Fryer Salmon.
Other Squash Recipes
If you love the simplicity of this summer squash casserole, make sure to check out these other easy squash recipes that are perfect for using up this summer produce.












Your zucchini and yellow squash casserole was a big hit. I made it on Christmas Day to my immediate family!! Thank you. No changes nor ingredient substitutions were made.
Thank you so much, Nelly! I love that you made it for Christmas Day — that’s such a compliment. I’m so glad it was a hit with your family, and it means a lot that it worked perfectly just as written.
Can I add a bit of chopped onion or a thin slice of onion between every two to three slices of squash/zucchini?
Hi Dorothy! That sounds delicious. I don’t see why you couldn’t. Let me know how it turns out.
A friend gave me several zucchini & yellow crooked neck squash from her garden. I sure didn’t want to let them go to waste since I live alone. Found this recipe online and decided to make it. It did not disappoint. The texture was perfect, the squash slices were tender, but kept their shape and with the crumb in Parmesan cheese topping, it was very tasty. I will make this again.
Yay! So happy to hear you enjoyed the recipe, Linda! I’m so glad you were able to use up squash before going bad and liked the dish! Thanks so much for taking the time to leave a comment and rating!
My non squash husband enjoyed this casserole!
I’ll be making it again
TX for this recipe
Yay! So happy to hear you enjoyed the recipe, Barbara! It’s deceptively delicious. Thanks so much for taking the time to leave a comment and rating!
This was really delicious I substituted the parsley with basil and cooked twice as long because we like our veggies soft
Husband loved loved it
Yay! So happy to hear you enjoyed the recipe! Thanks so much for taking the time to leave a comment!
Was very good, made it for a potluck, came back with empty dish.
Woohoo!! An empty dish is always a HUGE win in my book! (Although kind of sad, because leftovers are the best!) Thanks so much for taking the time to leave a comment letting me know how it turned out!
Delicious,,great presentation color, light eating. I like the fact that you can freeze it also. Thank you
Yay, Diane!! So so happy you enjoyed it. It does make the perfect summer dish 🙂 Thanks for taking the time to leave a comment and rating!
Excellent! I will definitely make this again.
Yay! So happy to hear you enjoyed the recipe, Collette! Thanks so much for taking the time to leave a comment!
Do you think I could also layer sweet onion slices and mushrooms into the mix?
That sounds delicious! Just be sure to cook the onions beforehand or they’ll be crispier than the other veggies. Let me know how it turns out.
The squash casserole was great! I made it with seasoned GF bread crumbs, so I left out the addition of garlic powder. I only used summer squash as it was most abundant in my garden. No zucchini this year! Everyone at the small gathering loved it and wanted the recipe! I’ll be looking forward to trying more of your recipes in the future. I’m making this one again tomorrow for company! Thank you!
Yay! So happy to hear you enjoyed the recipe, Carol! I’m so glad you could make it work. Thanks so much for taking the time to leave a comment!
I did make this recipe and it was delicious 😋. Will definitely use this again this summer 🌞
Yay! So happy to hear you enjoyed the recipe, Regina! It’s a great recipe for the summer. Thanks so much for taking the time to leave a comment!