There's nothing quite like the comforting taste of a Cheesy Zucchini Casserole fresh out of the oven. This hearty, creamy dish is packed with tender zucchini, melty cheese, and a perfectly crispy topping. It's a side dish that's as satisfying as it is versatile.

I first made this casserole during a summer zucchini surplus, and it quickly became a staple at family dinners and potlucks. Whether you're a seasoned cook or a beginner in the kitchen, this recipe is sure to become a favorite. Let’s dive into what makes it so irresistible!

Why You'll Love This Cheesy Zucchini Casserole

Get ready to fall in love with a dish that's equal parts indulgent and practical. This Cheesy Zucchini Casserole has everything you could want in a side dish and more.

First, it’s an excellent way to use up an abundance of zucchini. Whether it’s from your garden, the farmer's market, or a grocery store sale, this recipe ensures none of that fresh zucchini goes to waste.

Second, it's simple to make. With just a handful of pantry staples and about 15 minutes of prep, you can whip this dish together and let the oven do the rest. It's perfect for busy weeknights or casual gatherings.

And let’s talk about the texture – tender zucchini slices layered with rich, gooey cheese and topped with a crunchy, golden breadcrumb crust. Every bite is a delightful balance of creamy and crispy.

Finally, it’s incredibly versatile. Serve it as a standalone vegetarian dish or as a side to roasted chicken, grilled steaks, or your favorite protein. It complements just about anything!

Ingredients Notes

The secret to this Cheesy Zucchini Casserole lies in its fresh, flavorful ingredients. Here’s what you’ll need and why each is essential to the recipe.

Zucchini: The star of the show. Choose medium-sized zucchini with smooth, unblemished skin. They should feel firm and heavy for their size, indicating freshness.

Cheese: A mix of shredded mozzarella and sharp cheddar creates a perfect balance of melty creaminess and tangy flavor. Feel free to experiment with other cheeses like Monterey Jack or Parmesan for a different twist.

Breadcrumbs: These form the crispy topping that makes the casserole so irresistible. Panko breadcrumbs work best for an extra-crunchy finish, but regular breadcrumbs will do the trick as well.

Eggs and Milk: This duo binds the casserole together while keeping it light and fluffy. For a richer casserole, use whole milk or even a splash of cream.

Garlic and Onion: Minced garlic and finely chopped onion add depth of flavor to the casserole. Sauté them lightly before mixing for an even better taste.

If you have a mandoline slicer, it’s a great tool to quickly and evenly slice the zucchini. A shallow casserole dish or an 8x8 baking dish will also come in handy for even cooking.

How To Make This Cheesy Zucchini Casserole

Creating this Cheesy Zucchini Casserole is easier than you might think. Here’s how to bring it together step by step.

Start by preheating your oven to 375°F and lightly greasing your casserole dish. This ensures nothing sticks, making cleanup a breeze.

Slice your zucchini into thin, even rounds. You want them about ¼-inch thick so they cook evenly and absorb the cheesy goodness without turning mushy.

In a large skillet, sauté the chopped onion and garlic in a bit of olive oil until softened and fragrant. This step helps mellow their flavors and adds a savory base to the casserole.

In a mixing bowl, whisk together the eggs and milk. Add a pinch of salt, pepper, and a sprinkle of Italian seasoning for a hint of herby flavor.

Now it’s time to assemble. Layer the zucchini slices in the greased casserole dish, slightly overlapping them like shingles. Pour the egg mixture over the zucchini, then sprinkle half of your shredded cheese over the top.

Add a second layer of zucchini slices, followed by the remaining cheese. Finally, spread the breadcrumbs evenly across the top, and drizzle with a bit of melted butter to encourage browning.

Bake the casserole for 25-30 minutes, or until the top is golden brown and the cheese is bubbling. Let it cool for a few minutes before serving – it’ll smell amazing, but this step helps the layers set.

Storage Options

This Cheesy Zucchini Casserole is as easy to store as it is to make, making it a great candidate for meal prep or leftovers.

If you have leftovers, transfer them to an airtight container and refrigerate for up to 3 days. The casserole holds up beautifully when reheated, though the topping may lose a bit of its crispness.

To freeze, assemble the casserole as directed but stop before baking. Wrap the dish tightly in plastic wrap and foil, then freeze for up to 2 months. When ready to serve, bake straight from frozen, adding an extra 10-15 minutes to the cooking time.

For reheating, pop individual portions in the microwave for 1-2 minutes, or reheat the entire dish in the oven at 350°F for about 15 minutes.

Variations and Substitutions

This casserole is a blank canvas for creativity! Here are a few ways you can switch things up.

Swap the zucchini for yellow squash or a mix of both for a colorful twist. They cook similarly and pair just as well with cheese.

Add a protein like cooked, crumbled sausage or diced chicken to make it a more filling main course.

For a gluten-free version, use gluten-free breadcrumbs or crushed pork rinds for the topping. You won’t miss the crunch!

Experiment with different cheeses to suit your taste. Gruyere, fontina, or even a smoky gouda would elevate this dish to gourmet territory.

Mix in a handful of fresh herbs like parsley or basil for a burst of freshness, or a pinch of red pepper flakes for a touch of heat.

Whether you're sticking to the classic recipe or putting your own spin on it, this Cheesy Zucchini Casserole is a guaranteed crowd-pleaser. It's proof that simple ingredients and a little love can create something truly special. Happy cooking!