Cook noodles according to package directions. Meanwhile, in a large nonstick skillet, saute the onion, celery and garlic in oil until softened. Add the mushrooms; cook for 2-3 minutes. Stir in tomato sauce, tomato paste, sugar and seasonings; simmer for 10 minutes. In a bowl, combine the cottage cheese, egg, parsley and salt.
Drain noodles. Spread 1/2 cup of the sauce in a 13x9-in. baking dish coated with cooking spray. Layer with 4 noodles, half of the cottage cheese mixture, half of the spinach, a third of the remaining sauce and a third of the mozzarella. Repeat layers.
Top with remaining noodles, sauce, mozzarella and Parmesan. Cover and bake at 350° for 35 minutes. Uncover; bake 10 minutes longer. Let lasagna stand for 15 minutes before cutting.
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