3-Cheese Vegetable Lasagna (no meat involved)

1 large onion, chopped
3 cloves of garlic, minced
1 tsp. olive oil
1 (28 oz.) can tomatoes, tomato puree
1 (14.5 oz.) can tomatoes, un drained and chopped
2 cups (6 oz.) sliced fresh mushrooms
1 zucchini, diced
1 large green bell pepper, chopped
2 tsp. basil, crushed
1 tsp. salt (optional)
1/2 tsp. red pepper flakes
1/2 tsp. oregano, crushed
2 cups (15 oz.) Sargento light Ricotta cheese
1 (10 oz.) package frozen chopped spinach, thawed and squeezed dry
2 egg whites
2 Tbsp. Sargento Fancy Supreme shredded Parmesan Cheese (I use regular)
1/2 pound Lasagna noodles, cooked
3/4 cup (3 oz.) mozzarella (divided)
3/4 cup mild cheddar cheese (divided)
*You can use generic ingredients. This recipe is from, Favorite Brand Name BEST LOVED RECIPES of all time (so they work with brand name ingredients.)

Spray skillet with nonstick vegetable spray. Add onion, garlic and olive oil; cook over medium heat until tender, stirring occasionally. Add tomato puree, tomatoes, tomato liquid, mushrooms, zucchini, bell pepper, basil, salt, sugar, pepper flakes and oregano. Heat to a boil. Reduce heat; cover and simmer 10 minutes or until vegetables are crisp-tender.
Combine Ricotta cheese, spinach, egg whites and Parmesan cheese; mix well. Spread 1 cup sauce in bottom of a 9 by 13 baking dish. Layer 3 lasagna noodles over sauce. Top with half of ricotta cheese mixture and 2 cups sauce. Combine mozzarella cheese and cheddar cheese. Sprinkle 3/4 cup cheese mixture over sauce. Top with remaining lasagna noodles and sauce. Cover with foil; bake at 375 degrees for 30 minutes. Uncover; bake 15 minutes longer. Sprinkle with remaining 3/4 cup cheese mixture. Let stand 10 minutes before serving. This is sooo yummy, we love it.