In a large skillet, brown beef with onion, garlic and salt. Stir in spaghetti sauce, simmer until heated. Remove 1 cup of meat sauce, set aside. Stir noodles into the remaining sauce. Place half of noodle-sauce mixture in greased 2qt casserole. Cover with cottage cheese and 1 cup mozzarella cheese. Add remaining noodle-sauce mixture, top with 1 cup of reserved meat sauce and remaining mozzarella cheese. Sprinkle with Parmesan cheese.