Wash the meat if necessary and pat dry well. Season with salt and pepper. Fry in hot clarified butter for about 5 minutes on each side. Brush the top with mustard.
2 Roast 2 roast beef in the preheated oven (electric cooker: 200°C/circulating air: 175°C/gas: level 3) for 30-40 minutes. Let meat cool down.
Mix sour cream, mayonnaise, lemon juice, salt and pepper. Clean the radishes. Wash the radishes and chives. Cut both finely. Wash the cress and cut from the bed. Stir everything into the sour cream.
Cut roast beef into thin slices and arrange on a plate. Add the radish dip.