Step 1

Combine the soy sauce, vinegar, sherry, sugar and sesame oil in a small jug.

Step 2

Preheat oven to 180°C. Heat the olive oil in a large frying pan over medium-high heat. Season the beef with salt and pepper. Add the beef to the pan and cook, turning occasionally, for 10 minutes or until browned. Transfer to a baking tray. Bake for 15 minutes for medium-rare or until cooked to your liking. Transfer to a wire rack over a plate to cool completely.

Step 3

Transfer the beef to a large sealable plastic bag. Add the soy sauce mixture and turn to coat. Place in the fridge for 4 hours or overnight to marinate.

Step 4

Arrange the watercress on a serving platter. Thinly slice the beef and arrange on top of the watercress. Drizzle over any remaining soy sauce mixture.