1. To make the sauce, combine the mayonnaise, sour cream and horseradish in a small bowl and stir to mix well. Set aside. 2. Lay the bread slices out on a flat surface and spread each one with some of the sauce. Place 2 oz of roast beef on each of 4 bread slices, then top the roast beef with some of the cheese, a slice of tomato, a slice of onion, and a lettuce leaf. 3. Place the remaining bread slices on the sandwiches, cut each sandwich in half and serve immediately. ---------------------------------------------------------------------------
Nutrition
Ingredients