- 1 butter, softened
- 3 1/2 tablespoons prepared horseradish
- 3 tablespoons chopped fresh mint
- 8 small potato rolls
- 8 thin slices roast beef
- 1 bunch watercress
In food processor, pulse butter, horseradish and mint until smooth; season. Spread on potato rolls. Top roll bottoms with beef and watercress; add roll tops.