Rub the beef with oil and season with salt and freshly ground black pepper.
Heat a heavy-based frying pan and fry the beef for one minute on each side. Remove from the pan and set aside.
For the marinade, mix together all the ingredients in a bowl until well combined. Place the meat into the bowl and massage the marinade into the meat.
Transfer the meat and marinade into a sealable plastic bag and leave in the fridge to chill for at least two hours.
Meanwhile, for the dressing, whisk together all the ingredients in a bowl until well combined..
Arrange the salad on individual plates, or a large wooden board, and spoon over the dressing.
Once the meat has been chilled, slice it very thinly and arrange on top of the salad.