1. Heat oven to 375 degrees F.For Sauce::
2. Heat oil in large skillet over medium-high heat. Add mushrooms, zucchini and onion; cook 6 to 7 minutes or until tender. Stir in spaghetti sauce, diced tomatoes with liquid, oregano and pepper; set aside.
3. Lightly coat a 13x9-inch glass baking dish with vegetable cooking spray. Combine ricotta, Parmesan, egg, parsley and salt in medium bowl.
4. Spread 2 cups of the Sauce over bottom of prepared dish. Arrange 4 or 5 uncooked lasagna noodles lengthwise and slightly overlapping on top. Spread all of ricotta mixture over top to cover; sprinkle evenly with 1-1/2 cups of the mozzarella. Pour 1-1/2 cups of the Sauce on top. Repeat layering remaining noodles over Sauce. Top with remaining Sauce; sprinkle with remaining mozzarella.
5. Cover with foil and bake 20 minutes. Uncover and bake 20 to 25 minutes more or until bubbly. Let stand 10 minutes before serving. Makes 8 servings.