In a large skillet, cook turkey, mushrooms, pepper and onion over medium heat 6-8 minutes or until turkey is no longer pink and vegetables are tender, breaking turkey into crumbles; drain. Stir in garlic; cook 1 minute longer.
Stir in beans, salsa, green chilies, chili powder, cumin, salt and pepper sauce. Cook, uncovered, 4-5 minutes or until heated through. Add cheese and corn; heat through. Spread about 1/3 cup filling over each tostada shell. Sprinkle with lettuce, tomatoes and cilantro.
Freeze option: Freeze cooled meat mixture in freezer containers. To use, partially thaw in refrigerator overnight. Heat through in a saucepan, stirring occasionally and adding a little water if necessary. Serve on tostada shells with toppings.Yield: 8 servings.