Roast sesame seeds in a pan without fat, remove. Mix sesame, sesame oil, soy sauce and honey, put aside. Wash the meat and pat dry. Heat 2 tablespoons of oil in a large frying pan.
Brown the meat in it all around for 3-4 minutes. Season the meat with salt and pepper, place it on a baking tray and pour over the roast. Cook in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for 10-12 minutes in medium heat.
Meanwhile wash the apple, cut it in half, remove the core and cut it into small cubes. Place the apple cubes in lemon juice. Mix vinegar and horseradish and season with salt, pepper and sugar. Add 3 tablespoons of oil drop by drop.
Drain the apple cubes in a sieve and add to the horseradish vinaigrette. Clean, wash and pluck the salad into bite-sized pieces. Clean, wash and cut the peppers into thin strips. Clean and clean the mushrooms and cut them into wafer-thin slices.
Mix salad, mushrooms, peppers and vinaigrette. Remove the meat from the oven, wrap in aluminium foil and leave to rest in a warm place for about 5 minutes. Cut the meat into slices and marinate in the sesame marinade for about 5 minutes.
Arrange salad and meat on plates.