Made with fresh zucchini, panko breadcrumbs, and lots of cheese, this Baked Zucchini Casserole is an easy, cheesy side dish guaranteed to become a family favorite. With just 15 minutes of prep, it comes together quickly and the light, cheesy flavor pairs with just about anything.
An Easy, Cheesy Zucchini Casserole
There’s always a few weeks in the summer where there’s more than an abundance of zucchini around and when this cheesy zucchini casserole graces my table many times – it’s one of my go-to zucchini recipes. It’s loaded with cheese, which is my secret weapon to getting those who aren’t a fan of vegetables to enjoy eating them. In fact, this recipe comes with high approval and a demand for seconds from everyone in my family.
Cheesy zucchini casserole is simple to make, with only a handful of ingredients and steps before popping it in the oven. It bakes for just long enough to grill up your favorite chicken or steak and maybe toss together a simple salad. With its cheesy flavor, this casserole will go with just about everything. It’s a great go-to for nights when you aren’t sure what to make as a side dish.
Zucchini Casserole Recipe
Besides the fresh zucchini, this casserole requires only a handful of other ingredients and seasonings. The ingredients are simple but when put together they make a tasty, cheesy dish you won’t be able to get enough of!
(Scroll below to the printable recipe card for details and measurements.)
- Butter – Salted butter for the extra flavor.
- Zucchini – 3 medium-sized zucchinis is the perfect amount for this casserole. Fresh from the garden or from the farmers’ market is ideal.
- Sweet onion – Adds texture, flavor, and a subtle sweetness.
- Seasonings – Simple seasonings include fresh minced garlic, dried Italian seasoning, and kosher salt. Fresh parsley is also added at the end for a pop of color and taste.
- Cheese – A combination of sharp cheddar cheese and Swiss or Monterrey Jack for an extra cheesy casserole with a variety in flavor.
- Panko crumbs – Italian seasoned panko bread crumbs add flavor and a light, crispy texture.
- Use yellow squash instead of zucchini. This can also be made with yellow squash or a combination of the two.
- Switch up the cheese. While I love the sharp flavor of cheddar and the contrast of Swiss, you may use your preferred cheese in this casserole. A bit of parmesan is a great addition!
- Double for a crowd. If you need more than 4 servings, you can easily double this recipe and bake it in a bigger dish. You may need to slightly adjust the cooking time but otherwise, everything will stay the same.
- Make it gluten-free. Swap the panko breadcrumbs for gluten-free breadcrumbs to make this casserole gluten-free.
How to Make Baked Zucchini Casserole
Once the vegetables are sliced, this zucchini casserole comes together quickly. After it goes in the oven you have just enough time to finish preparing the rest of your dinner before this cheesy delight is ready to enjoy. Here’s a brief summary:
(Scroll below to the printable recipe card for details.)
- Sauté the vegetables. Quickly sauté the zucchini, onion, garlic and seasonings in melted butter until they begin to soften. Remove from heat and stir in cheddar cheese.
- Assemble the casserole. Transfer the zucchini mixture to a prepared baking dish, then sprinkle with cheese.
- Bake. Bake until bubbly, add the panko crumb topping, and return to the oven for an additional 10 minutes. Garnish with parsley and serve.
Use a Mandolin to Slice the Zucchini
This baked zucchini casserole is great served as a side dish to a flavorful protein, like Salisbury Steak, skillet steak, pan fried pork, or baked chicken breasts. It also pairs nicely with a simple side salad, which adds a pop of color to your plate and balances the richness of the cheesy casserole.
How to Store Leftovers
If you have leftovers, cool completely, then store in airtight container in the refrigerator for up to 3 days. (Freezing is not recommended. Zucchini holds a lot of water, even after it’s cooked, and will release much of that water when it thaws which can make the texture of the casserole unappetizing.)
More Zucchini Recipes:
- Zucchini Bread
- Air Fryer Zucchini Fries
- Zucchini Ricotta Pancakes
- Italian Stuffed Zucchini
- Zucchini Lasagna Rolls
Baked Zucchini Casserole
- 4 tablespoons butter , divided
- 3 medium zucchini (sliced 1/4 inch thick)
- 1/2 cup sweet onion , diced
- 1 clove garlic , minced
- 1 teaspoon dried Italian seasoning
- 1/2 teaspoon kosher salt
- 1 cup shredded sharp cheddar cheese
- 3/4 cup shredded Swiss (or Monterrey Jack cheese)
- 1 cup Italian seasoned Panko bread crumbs
- chopped fresh parsley , for garnish
- Preheat oven to 350 degrees F. Coat a 9×9-inch baking dish with nonstick cooking spray; set aside.
- In a large nonstick skillet, warm 2 tablespoons of the butter over medium-high heat. Add in the zucchini, onion, garlic, Italian seasoning, and salt; sauté for 3-4 minutes or until vegetables have started to soften.
- Take pan off heat and stir in the cheddar cheese.
- Spoon the zucchini mixture into the prepared baking dish.
- Sprinkle the Swiss (or Monterey Jack) cheese over the top.
- Cover with foil and bake for 15-20 minutes until the casserole is bubbly.
- Melt the remaining 2 tablespoons of butter and mix with the Panko bread crumbs until coated. Uncover casserole and sprinkle over the top.
- Return to the oven, uncovered, and bake another 10 minutes until the Panko is golden brown.
- Garnish with chopped parsley, optional.
- Serve and enjoy!