This Baked Ziti recipe can be made ahead of time, making it a great go-to dish for weeknight meals or for an easy lunch!
Cook ziti according to package directions; drain. Set aside.
Preheat oven to 375º F.
Heat oil in a large nonstick skillet over medium-high heat.
Add onion; cook, stirring frequently, for 4 to 6 minutes, or until onion is translucent.
Add garlic; cook, stirring frequently, for 1 minute.
Add tomatoes, summer squash, and zucchini; cook, stirring frequently, for 3 to 4 minutes.
Combine onion mixture, pasta, basil, salt, pepper, red pepper flakes (if desired), ½ cup mozzarella cheese, Parmesan cheese, and ricotta cheese in a large bowl; mix well. Place in a 2½ to 3-quart casserole that is lightly coated with spray.
Top evenly with remaining ¼ cup mozzarella cheese. Bake, covered with aluminum foil, for 35 minutes. Remove foil and bake an additional 10 minutes, or until cheese is bubbly.
The Nutrition Facts box below provides estimated nutritional information for this recipe.