Zucchini Casserole

Name: Zucchini Casserole
Prep time: 10 min
Cook time: 25 min
Total time: 35 min
Cuisine: American
Ingredients: 1 1/2 Tablespoons extra virgin olive oil; 4 medium zucchinis (sliced round, about 6 cups); 1 medium onion (chopped); 2 large garlic cloves (chopped); 1 teaspoon Italian seasoning; 1 teaspoon sea salt; 3 1/3 cups Monterey jack cheese (divided); 1 1/2 cups cheddar cheese (old, mild, or sharp); 1 cup mayonnaise; 1 cup panko breadcrumbs; 2 Tablespoons unsalted butter (melted); chopped parsley (optional as garnish)