Melt butter in a large skillet over medium-high heat; add onion, bell pepper, and mushrooms, and sauté 13 minutes or until onions are golden brown. Add strips and garlic; sauté 3 minutes or until thoroughly heated. Stir in dressing, and, if desired, crushed red pepper. Season with salt and black pepper to taste.
Arrange strips mixture evenly on bottom roll halves; top with cheese and remaining roll halves. Arrange on a baking sheet. Bake at 400° for 8 minutes or until buns are toasted and cheese is melted.
