Zucchini & Squash Casserole
Ingredients
- 1 tablespoon unsalted butter, divided
- 1.5 pounds zucchini (about 4 medium), sliced 1/4 inch thick
- 1.5 cups thinly sliced yellow onion, divided
- 1.5 pounds small yellow squash, sliced 1/4 inch thick
- 2 large eggs
- 0.5 cup canola mayonnaise
- .25 cup pesto
- 0.125 teaspoon salt
- 0.5 cup shredded low-moisture mozzarella cheese
- 0.5 cup panko breadcrumbs
- 0.25 cup grated Parmesan cheese
- Cooking spray
Instructions
- Place oven rack in middle position; preheat to 375°F. Melt 1/2 tablespoon butter in a large nonstick skillet over medium-high heat. Add zucchini and 3/4 cup onion; cook, stirring often, until the center of the zucchini is very tender and translucent, 10 to 12 minutes. Transfer the mixture to a colander set over a bowl. Repeat with yellow squash and the remaining 1/2 tablespoon butter and 3/4 cup onion. Add the squash mixture to the colander with the zucchini; let drain for 5 minutes. Using a rubber spatula, gently stir and press down on the zucchini-squash mixture to extract as much liquid as possible without disfiguring the squash; discard liquid.
- Whisk eggs, mayonnaise, pesto and salt together in a large bowl. Gently fold in the zucchini-squash mixture and mozzarella. Spoon into a broiler-safe 2-quart baking dish.
- Combine panko and Parmesan in a small bowl; sprinkle evenly over the casserole. Lightly coat the panko mixture with cooking spray. Bake until golden brown in spots, about 30 minutes.
- Set oven to broil. (Do not remove casserole from oven.) Broil until the topping is golden brown all over, 2 to 3 minutes. Let stand for 5 minutes before serving.
