Start by pickling the shallots & radish in the sherry vinegar & sugar, then simply mix together & reserve. Heat a heavy based frying pan until smoking hot. Massage the beef with a little oil & season generously with salt & pepper. Sear the beef on both sides, 3-4 minutes in total then remove from pan & keep warm whilst assembling the salad. To Assemble Toss the rocket leaves in a little dressing then place onto 2 serving plates. Crumble the blue cheese over the salad. Slice the Beef into slivers & arrange with the salad & cheese. Scatter over the pickled shallots & radish, serve straight away.