Dinner

Squash Casserole Recipe

ByMariam Harutyunyan November 20, 2025November 20, 2025

Introduction

Squash casserole is a comforting, flavorful dish that highlights the natural sweetness of yellow squash and zucchini. With a crispy, cheesy topping and tender vegetables, it makes a perfect side for any meal.

A creamy baked casserole is shown in a white oval dish placed on a white marbled surface with a striped cloth beside it and a large spoon in the background. The casserole has three distinct layers: the bottom layer consists of a soft, white creamy base mixed with rice or grains, the middle layer has thick slices of green and yellow zucchini arranged in rows, some partially covered by the cream, and the top layer is a golden-brown, crispy crumb topping scattered evenly with a rough texture. The edges of the crumb layer are slightly darker, giving a toasted look. Photo taken with an iphone --ar 4:5 --v 7

Ingredients

1 small onion (sliced)
1 tablespoon butter

1 tablespoon olive oil
½ teaspoon Italian seasoning

2 pounds squash (yellow squash and zucchini)
Salt and pepper to taste

⅓ cup seasoned bread crumbs
¼ cup grated Parmesan cheese
¼ cup shredded cheddar cheese

2 tablespoons melted butter

Instructions

Step 1: Preheat the oven to 350°F (175°C).
Step 2: Slice the yellow squash and zucchini into ¼-inch thick slices.

Step 3: In a large skillet over medium heat, cook the sliced onion in butter and olive oil until tender. Increase the heat to medium-high, then add the squash, Italian seasoning, salt, and pepper. Cook for 5 to 6 minutes until the squash is tender-crisp.
Step 4: Grease a 2-quart baking dish. Arrange the cooked squash and onions in the dish with the squash slices standing on their side.
Step 5: In a small bowl, combine the seasoned bread crumbs, Parmesan cheese, cheddar cheese, and melted butter. Sprinkle this mixture evenly over the squash.

Step 6: Bake in the preheated oven for 35 to 40 minutes, or until the squash is tender and the topping is golden brown.

Tips & Variations

For extra flavor, add minced garlic when cooking the onions.
Try using a mix of different cheese varieties like mozzarella or Monterey Jack for a different twist.

To make it gluten-free, substitute the seasoned bread crumbs with gluten-free crumbs or crushed nuts.
Standing the squash slices upright helps them cook evenly and creates a nice presentation.

Storage

Store any leftover squash casserole in an airtight container in the refrigerator for up to 3 days. To reheat, warm it gently in the oven at 325°F until heated through to maintain the crispy topping.

How to Serve

The dish is shown in a gray oval baking dish sitting on a white marbled surface with a gray and white striped cloth nearby. It has about three visible layers: the top layer is a golden-brown crispy breadcrumb and melted cheese crust with uneven patches of deeper browning, the middle layer shows soft cooked green and yellow zucchini rounds mixed with a creamy sauce, and the bottom layer is mostly covered but looks creamy with bits of zucchini peeking through. A serving spoon rests beside the dish on a light wood board. photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I prepare the squash casserole ahead of time?

Yes, you can assemble the casserole a few hours before baking. Keep it covered in the refrigerator and bake when ready. You may need to add a few extra minutes to the baking time if it’s chilled.

Can I freeze squash casserole?

It’s best to freeze before baking for optimal texture. Assemble the casserole, cover tightly, and freeze up to 2 months. Thaw overnight in the fridge before baking as directed.