Extra wild rocket leaves, to garnish
Horseradish Cream
300g tub sour cream1 Season beef on both sides with salt and pepper. Heat oil in a flameproof roasting pan over a medium to high heat. Add beef. Cook for 3 minutes on each side, or until brown.
2 Transfer to oven. Cook in a hot oven (200C) for 12 to 15 minutes for rare. Remove. Transfer beef to a plate. Stand for 30 minutes. Refrigerate, covered, until cool. Thinly slice.
3 To make horseradish cream, combine all ingredients in a small bowl. Season. Mix well.
4 Spread horseradish cream over one side of each slice of bread. Divide beef and rocket over half the bread slices. Top with remaining bread slices, cream-side facing downwards.
5 Using a serrated or electric knife, cut the crusts off sandwiches. Cut each sandwich, diagonally, into quarters. Place on a serving plate. Cover and refrigerate until serving. Serve garnished with wild rocket leaves.