In a mixing bowl, combine beef ravioli, mushrooms, onions, cheese, Italian seasoning, and salt. Mix well. Spread in a 1-quart casserole dish. Sprinkle with croutons. Cover loosely and microwave until ravioli mixture is hot, 5 minutes.
Per serving: 135 Calories; 2g Fat (16% calories from fat); 9g Protein; 20g Carbohydrate; 9mg Cholesterol; 773mg Sodium