How to Make It
Preheat oven to 350°. Place bread slices on a baking sheet. Bake 8 to 10 minutes or until toasted.
Meanwhile, stir together sour cream and next 3 ingredients in a small bowl.
Top each bread slice with chopped roast beef, sour cream mixture, and blue cheese. Sprinkle with freshly ground pepper. Garnish, if desired.