It happens every summer: the zucchini and yellow squash take over. Whether you’re a backyard gardener or a generous farmer’s market regular, you end up with more squash than you know what to do with. Enter this cheesy squash bake—a warm, comforting dish that lets those summer veggies shine while adding a little indulgent flair.
This casserole is everything we love about summer wrapped into one: sweet corn, tender squash, a creamy filling, and a golden, cheesy topping that will have your family fighting over seconds. It’s perfect as a main for meatless nights or as a hearty corn zucchini side dish at any BBQ.
Why You’ll Love This Zucchini Squash Corn Casserole
- A great way to use up summer produce
- Family-friendly and potluck-perfect
- Make-ahead friendly and freezer-friendly
- Comfort food with a fresh twist
Ingredients
- 1½ lb yellow squash, thinly sliced
- 1½ lb zucchini, thinly sliced
- 1/4 cup butter, divided
- 2 cups diced sweet onion
- 2 garlic cloves, minced
- 3 cups corn kernels
- 1½ cups shredded white cheddar cheese
- 1/2 cup sour cream
- 1/2 cup mayonnaise
- 2 large eggs, lightly beaten
- 2 tsp black pepper
- 1 tsp salt
- 1½ cups fresh breadcrumbs, divided
- 1 cup grated Parmesan cheese, divided
How to Make Zucchini Squash & Corn Casserole
- Preheat oven to 350°F and grease a 9×13 baking dish.
- In a skillet, melt 2 tbsp butter. Sauté squash, zucchini, and onion for 10 minutes until tender. Add garlic and cook two more minutes. Let cool slightly.
- In a large bowl, mix cooked veggies with corn, cheddar, sour cream, mayo, eggs, salt, pepper, 1/2 cup breadcrumbs, and 1/2 cup parmesan.
- Spread the mixture into the prepared dish.
- Melt the remaining 2 tbsp butter and mix with the remaining breadcrumbs and parmesan. Sprinkle over the casserole.
- Bake uncovered for 45–50 minutes until golden and bubbling. Cool slightly before serving.
Tips for the Best Cheesy Squash Bake
- Slice the squash thinly so it blends well into the creamy filling.
- No fresh corn? Frozen or canned works too.
- Add a sprinkle of crushed red pepper for a little heat.
- Want to lighten it up? Use Greek yoghurt instead of sour cream.
From Olivia’s Garden to Your Table
One summer, my squash plants basically turned into jungle vines, and I needed a delicious way to use them up fast. After a few trials (some more successful than others), this casserole emerged as the hands-down winner. It’s the recipe I make when friends come over for a casual dinner on the porch, and it always brings rave reviews and recipe requests.
What to Serve with This Corn Zucchini Side Dish
This casserole pairs beautifully with grilled meats like chicken or pork chops. It also works as a stand-alone dish next to a fresh salad for a lighter meal. Planning a potluck? It holds up well at room temperature and makes a generous batch for sharing.
How to Store and Reheat
Let the casserole cool completely before covering and refrigerating. It keeps well for 3–4 days. Reheat individual portions in the microwave, or pop the whole dish in the oven at 350°F until warm. It also freezes beautifully—just wrap tightly and label for up to 2 months.
FAQs
Can I make this ahead of time?
Yes! Assemble it a day in advance and refrigerate until ready to bake.
Can I use different cheeses?
Absolutely. Sharp cheddar or a blend with mozzarella adds great flavour.
Can I add protein to make it a full meal?
You bet. Stir in cooked chicken or turkey sausage before baking.
How do I keep the casserole from getting watery?
Make sure to sauté the squash well to remove moisture and let the mixture cool slightly before baking.
Zucchini Squash Corn Casserole: The Creamy Crowd-Pleaser of Summer
This dish is everything you want in a summer vegetable casserole: comforting yet fresh, easy yet impressive, and just indulgent enough to feel like a treat. With golden bubbly cheese, sweet bursts of corn, and that satisfying savoury squash, it’s bound to be the star of your summer table.
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Zucchini Squash & Corn Casserole: A Creamy, Cheesy Summer Classic
- Total Time: 1 hour 10 minutes
- Yield: 8–10 servings 1x
- Diet: Vegetarian
Description
Zucchini Squash Corn Casserole is a creamy, cheesy, golden-topped bake filled with summer vegetables like tender zucchini, yellow squash, and sweet corn. It’s the ultimate comfort food-meets-garden-fresh dish—perfect as a hearty vegetarian main or a show-stopping summer side.
Ingredients
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1½ lb yellow squash, thinly sliced
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1½ lb zucchini, thinly sliced
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1/4 cup butter, divided
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2 cups diced sweet onion
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2 garlic cloves, minced
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3 cups corn kernels
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1½ cups shredded white cheddar cheese
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1/2 cup sour cream
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1/2 cup mayonnaise
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2 large eggs, lightly beaten
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2 tsp black pepper
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1 tsp salt
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1½ cups fresh breadcrumbs, divided
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1 cup grated Parmesan cheese, divided
Instructions
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Preheat oven to 350°F and grease a 9×13-inch baking dish.
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In a skillet, melt 2 tbsp butter. Sauté squash, zucchini, and onion for 10 minutes until softened. Add garlic and cook 2 more minutes. Let cool slightly.
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In a large bowl, mix the cooked vegetables with corn, cheddar, sour cream, mayonnaise, eggs, salt, pepper, 1/2 cup breadcrumbs, and 1/2 cup parmesan cheese.
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Spread the mixture into the prepared baking dish.
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Melt remaining 2 tbsp butter and mix with remaining 1 cup breadcrumbs and 1/2 cup parmesan. Sprinkle over the top.
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Bake uncovered for 45–50 minutes, until golden brown and bubbling. Let cool slightly before serving.
Notes
Sauté the squash well to reduce moisture and avoid a watery casserole.
Frozen or canned corn can be used if fresh isn’t available.
Add red pepper flakes for an extra kick or substitute sour cream with Greek yoghurt for a lighter twist.
Easily made ahead or frozen for later meals.
- Prep Time: 20 minutes
- Cook Time: 50 minutes
- Category: Casserole
- Method: Baking
- Cuisine: American