Dab steaks dry, cut into small cubes and put them on skewers. Mix soy sauce, brown sugar and 1-2 tbsp. oil. Brush the meat skewers with it. Cover and chill for about 30 minutes.
Peel and chop the shallot. Mix with ketchup, plum jam and Sambal Oelek. Season with salt and sugar. Clean, wash and drain the salad. For the marinade, beat vinegar, 1 pinch of sugar, salt, pepper and 1-2 tbsp. oil.
Roast the sesame seeds in a pan until golden brown and take them out. Heat 1 tablespoon of oil in the pan. Fry the skewers for 2-3 minutes. Remove and sprinkle with sesame seeds.
Mix salad and marinade and divide into four plates. Arrange meat skewers on top and serve with the plum dip.