PREPARATION:

1. Preheat oven to 375°F. Spray 13X9-inch baking dish or lasagna pan with nonstick cooking spray.
2. Heat oil in large skillet over medium heat until hot. Add zucchini, mushrooms, onion and garlic. Cook and stir 5 minutes or until vegetables are tender. Set aside.
3. Combine ricotta cheese, eggs, Parmesan cheese, Italian seasoning, garlic salt and pepper in medium bowl. Combine tomatoes and spaghetti sauce in another medium bowl.
4. Spread about 3/4 cup tomato mixture in prepared dish. Place layer of noodles over tomato mixture, overlapping noodles. Spread half of vegetable mixture over noodles; top with half of ricotta mixture. Sprinkle 1 cup mozzarella over ricotta mixture. Place second layer of noodles over mozzarella. Spread about 1 cup tomato mixture over noodles. Top with remaining vegetable and ricotta cheese mixtures. Sprinkle 1 cup mozzarella over ricotta mixture. Place third layer of noodles over mozzarella. Spread remaining tomato mixture over noodles. Sprinkle remaining 2 cups mozzarella evenly over top.
5. Cover tightly with foil and bake 1 hour or until noodles in center are soft. Uncover; bake 5 minutes or until cheese is melted and lightly browned. Remove from oven; cover and let stand 15 minutes before serving.