Garlic Parmesan Zucchini Casserole

This Garlic Parmesan Zucchini Casserole is an easy side dish recipe that pairs beautifully with just about any family meal!

This zucchini casserole has quickly become a favorite among the boys in my house!

I’m telling you: if you want to get your kids (or your husband) to eat some green vegetables, then THIS is the recipe for you. The zucchini is mild, it’s baked with three different kinds of cheese, and it’s finished with a buttery Parmesan breadcrumb topping. What’s not to love?!


Zucchini naturally holds a lot of water so you’ll probably notice as it cooks a lot of water is released. This can be a problem when adding them to casseroles, bakes, and sauces as it can water down the sauce and texture causing a bland flavor.

If you sprinkle the zucchini with salt and allow them to sit for 10 minutes the salt will draw out a lot of moisture so you won’t have that problem.

TIP: In order to make sure that I get most of the water out of the zucchini (and avoid a runny casserole), I like wrap the zucchini in a dish towel. Squeeze it and wring it out multiple times while it’s in the towel — you will be shocked by how much liquid comes out!

  • 4 cups grated zucchini (about 3.5 medium zucchinis)
  • 1/2 teaspoon salt
  • 1/2 cup finely diced onion
  • 1 tablespoon minced garlic
  • 2 eggs
  • 1/2 cup grated parmesan cheese, plus an additional 2 tablespoons
  • 1 cup shredded mozzarella cheese
  • 1/2 cup shredded cheddar cheese
  • 1/2 cup Panko breadcrumbs
  • 2 tablespoons melted butter


  1. Preheat oven to 375 degrees. Spray a small baking dish with cooking spray.
  2. Place zucchini in a colander, sprinkle with salt, and allow to sit for about 10 minutes (this will help draw out some of the water from the zucchini). After 10 minutes, squeeze out moisture from the zucchini.
  3. In the prepared dish, combine zucchini, onion, garlic, eggs, 1/2 cup Parmesan cheese, mozzarella cheese, and cheddar cheese until combined. Gently press the mixture evenly into the prepared dish.
  4. Bake uncovered for 20 minutes.
  5. Meanwhile, in a small bowl, pour melted butter over breadcrumbs and 2 tablespoons of Parmesan cheese. Stir until completely combined.
  6. After 20 minutes, remove zucchini from the oven. Sprinkle buttered breadcrumbs over the zucchini and return the dish to the oven. Continue baking for about 5-10 more minutes, or until the top is golden brown and crispy.