1. Preheat broiler.
2. Combine first 5 ingredients in a bowl; stir well.
3. Coat both sides of bread slices with cooking spray. Place half of bread slices in a single layer on a large baking sheet. Broil 1 1/2 minutes on each side or until lightly toasted. Repeat procedure with remaining bread.
4. Spread 1 teaspoon cheese over 1 side of each slice of bread. Divide beef evenly among bread slices; top each with 1 teaspoon bell pepper mixture. Serve immediately.