Summer Squash Casserole with Zucchini and Corn
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This Summer Squash Casserole is creamy, cheesy, packed with seasonal vegetables, and finished with a golden, crunchy topping that’s absolutely irresistible. It’s the kind of dish that even the squash skeptics will love!
Sheila’s Recipe Snapshot for Squash Casserole
This cozy, cheesy casserole is the ultimate way to turn fresh summer veggies into something everyone will love—even the picky eaters.
Served hot and bubbly, this cheesy squash casserole is a delicious way to put your summer produce to good use. Made with a mix of zucchini, yellow squash, and sweet corn, the filling is creamy but not heavy—no mayo, no cream soup, and no eggs. Just sour cream, cheese, and lots of flavor!
For me, the best part is definitely the topping. A buttery mix of herb-seasoned stuffing and Parmesan crisps up in the oven for a gratin-like finish that adds the perfect crunchy contrast to the vegetables!
This recipe came to life thanks to a growing pile of squash in our weekly produce box and a husband who claimed he didn’t like squash. But when I made this for a family cookout, he surprised us all by going back for seconds. Proof that a little cheese and a golden topping can convert just about anyone.
I’ve already made this dish twice this summer and plan to keep it on repeat as long as the squash continues to come in! It is a superb side dish for summer picnics or potlucks and goes well with grilled chicken, glazed pork tenderloin, or even electric smoker ribs!
Ingredient Notes for Squash Casserole with Zucchini
- Butter | Divided for sautéing and for mixing into the topping. Adds richness and helps crisp the topping.
- Onion & Garlic | Aromatics that build flavor from the start.
- Zucchini & Yellow Squash | Use fresh, firm squash and dice them evenly so they cook at the same rate.
- Fresh Corn | Adds a pop of sweetness and texture. One ear is plenty—just slice it off the cob.
- Sour Cream | Light sour cream keeps the filling creamy without being too rich.
- Cheddar Cheese | Adds sharp, melty goodness. You can also use a cheese blend if preferred.
- Kosher Salt & Black Pepper | Season to taste.
- Herb Seasoned Stuffing Mix | Packs in flavor and makes a quick, savory topping.
- Parmesan Cheese | Adds a nutty, salty kick to the topping.
Variations and Substitutions
- Squash: Use all yellow squash or all zucchini if you don’t have both.
- Corn: Frozen corn works if fresh isn’t available, just thaw and drain well.
- Sour Cream: Swap sour cream for plain Greek yogurt for a lighter version with more protein!
- Add-ins: Add red bell pepper, spinach, or mushrooms for extra veggies.
- Topping: Use crushed buttery crackers like Ritz or panko breadcrumbs instead of stuffing mix if needed.
How to Make Casserole with Zucchini and Squash
This recipe is so easy to put together—all you need is a skillet, a baking dish, and a few minutes to stir everything together before it goes in the oven!
PREHEAT & PREP. Preheat the oven to 350 degrees. Lightly coat a 9 x 13-inch baking dish with cooking spray. Prep the vegetables by dicing the squash and cutting the corn off the cob.
SAUTE THE AROMATICS. In a large skillet over medium heat, melt 2 tablespoons butter. Add the onion and cook for 5 minutes, until translucent. Then add the garlic and cook until fragrant, about 30 seconds.
SAUTE THE VEGGIES. Add the diced zucchini, squash, and corn to the skillet and cook for 5 minutes, stirring frequently.
ADD CHEESE & SOUR CREAM. Remove the skillet from the heat and stir in the sour cream, cheddar cheese, salt, and pepper. Pour the mixture into the prepared baking dish.
MAKE THE TOPPING. In a medium bowl, stir together the herbed stuffing mix, parmesan cheese, and 2 tablespoons melted butter. Sprinkle evenly over the casserole.
BAKE & ENJOY. Bake for 40 to 45 minutes, until the casserole is hot and bubbly. Let stand 10 minutes before serving.
More Recipe Success Tips
Storage and Reheating Tips
- Refrigerator: Let any leftovers cool completely before covering and refrigerating. The casserole can be stored in the refrigerator for up to 4 days.
- Reheating: To reheat, warm individual servings in the microwave or reheat the full dish in a 350ºF oven until hot. For the best texture, reheat uncovered in the oven so the topping stays crisp, but be careful not to let it get too brown.
Frequently Asked Questions
Yes, but the texture of the squash may soften a bit after thawing. Freeze before baking (without the topping) for best results. Add the topping just before baking.
Both yellow squash and zucchini are packed with vitamins and beneficial nutrients. Yellow squash is a power veggie boasting vitamins A, B6, and C, folate, magnesium, fiber, riboflavin, phosphorus, and potassium — whew!
Absolutely! When squash is bountiful, freezing it and saving it to use later is super easy to do. There’s no need to blanch it, just cut the squash into the size you’ll need for future recipes (diced, sliced, or shredded) and then seal it up raw in freezer bags. It will retain its flavor frozen for 4 to 6 months.
Looking for More Summertime Recipes?
This easy Greek orzo pasta salad and my elote corn recipe are both summertime family favorites. I have a Southern tomato pie recipe that is perfect for tomato season, too!
What to Serve With this Squash and Zucchini Recipe
This recipe for summer squash and zucchini casserole makes a perfect side dish for all kinds of Southern-inspired meals!
Serve it alongside juicy air fryer pork chops (no breading) or slow cooker country style ribs for a hearty dinner. It’s also delicious with electric smoker pulled pork, holiday ham, or a simple roasted chicken with potatoes.
Add classic Southern sides like a honey cornbread recipe or Southern homemade biscuits. No matter how you serve it, this casserole fits right in with all your favorite comfort foods!
Other Ways to Cook Summer Squash
With ALL that goodness and nutritional benefits, it’s a good idea to find more ways to include Summer squash in your family’s diet. Here are a few tasty ideas for how:
- IN LASAGNA. Healthy and super delicious, this Easy Skillet Vegetable Lasagna can be prepared AND cooked in less time than it takes to do the prep work (cooking the noodles and making the fillings) for a traditional baked lasagna.
- ON THE GRILL. Toss sliced zucchini, squash, onions, or peppers in olive oil and sprinkle with this easy Magic Rub recipe. Cook over direct heat for three or four minutes per side, or until the veggies are slightly charred and tender. EASY!
- BREADED AND BAKED. You’re gonna love how easy it is to make this healthy Baked Parmesan Squash.
- SPIRALIZED! How about this super simple recipe for Spiralized Pesto Noodles that can be done in a short amount of time? Delish!
- IN A QUICHE. This veggie lover’s California Quiche is chock full of zucchini, peppers, onion, and artichoke hearts. Big bonus: one serving is under 250 calories!
- IN A SALAD. Grilled Summer Vegetable Pasta Salad is a mixture of delicious pasta mixed with the cream of the summer crops veggies, like squash!
- IN QUICK BREAD. Hide veggies in this healthier, most delicious zucchini snickerdoodle quick bread and no one will ever be the wiser!
- IN CHOCOLATE CAKE! Super rich and fudgy; studded with chocolate chips, frosted with creamy, chocolate buttercream — nobody will even know there’s zucchini hidden inside this Chocolate Zucchini Cake!
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Summer Squash, Zucchini, and Corn Casserole
Ingredients
- 4 tablespoons unsalted butter divided
- ⅔ cup diced onion
- 1 clove garlic minced
- 3 cups diced zucchini squash 2 medium
- 3 cups diced yellow squash 2 medium
- 1 ear fresh corn cut off the cob
- 1 cup light sour cream
- 1 cup cheddar cheese shredded
- 1 teaspoon kosher salt
- ¾ teaspoon black pepper
- 2 cups dry herb seasoned stuffing mix like Pepperidge Farms
- ¼ cup grated parmesan cheese
Instructions
- Preheat the oven to 350 degrees. Lightly coat a 9 x 13 inch baking dish with cooking spray.
- In a large skillet over medium heat, melt 2 tablespoons butter. Add the onion and cook for 5 minutes, until translucent. Add the garlic and cook until fragrant, about 30 seconds.
- Add the diced zucchini, squash, and corn to the skillet and cook for 5 minutes, stirring frequently.
- Remove the skillet from the heat and stir in the sour cream, cheddar cheese, salt, and pepper. Pour the mixture into the prepared baking dish.
- In a medium bowl, stir together the herbed stuffing mix, parmesan cheese, and 2 tablespoons melted butter. Sprinkle evenly over the casserole.
- Bake for 40 to 45 minutes, until the casserole is hot and bubbly. Let stand 10 minutes before serving.
Notes
- I like the flavor of the herb seasoned stuffing mix for the breadcrumb topping, but you can also substitute panko breadcrumbs if desired.
- Refrigerator: Let any leftovers cool completely before covering and refrigerating. The casserole can be stored in the refrigerator for up to 4 days.
- Reheating: To reheat, warm individual servings in the microwave or reheat the full dish in a 350ºF oven until hot. For the best texture, reheat uncovered in the oven so the topping stays crisp, but be careful not to let it get too brown.
Nutrition
Life Love and Good Food does not claim to be a registered dietician or nutritionist. Nutritional information shared on this site is only an estimate. We recommend running the ingredients through an online nutritional calculator if you need to verify any information.
We really enjoyed this recipe. I made it using gluten free stuffing and a drained can of corn in lieu of fresh and it worked well. One suggestion – in step 4 you state “add cheese” but you didn’t specify which cheese so I put the parmesan in at this step then realize it should have been the cheddar cheese so perhaps edit that step to say “add cheddar cheese”. I ended up sprinkling on some cheddar on top before putting down the stuffing/butter/parmesan cheese layer. It still turned out very good – I mean, you can never have too much cheese! 😉
Janelle sorry for any confusion — I’ve updated the instructions — thank you so much for the head’s up! Glad you enjoyed the recipe, too!
My family loved this!