Cook onion and garlic in 10-inch skillet till soft. Remove from pan. Cook sausage, breaking into small pieces. Pour off grease. Add onions and garlic, noodles, tomato sauce and crushed tomatoes, and bring to a boil. Simmer till noodles are cooked, about 25 minutes. (Or cook in a medium oven, if needed.) Stir in spinach till wilted. Stir in cheeses and check seasoning. Stand for five minutes before serving.