1 lb london broil beef  | 
                                                1 (1 1/4 ounce) package taco seasoning mix  | 
                                                cooking spray  | 
                                                1 cup chopped onion  | 
                                                1 large bell pepper, sliced  | 
                                                2 chopped garlic cloves  | 
                                                2 tablespoons white vinegar  | 
                                                1 (4 1/2 ounce) can chopped green chilies  | 
                                                1 (16 ounce) can fat-free refried beans  | 
                                                8 (8 inch) fat free tortillas  | 
                                                3/4 cup shredded monterey jack cheese (you can also use kraft 2%)  | 
                                                1 1/2 cups chopped plum tomatoes  | 
                                                3/4 cup nonfat sour cream  |