Wash the liver, pat dry and cut into strips. Dust with flour. Clean the onions and cut into pieces 1-2 cm long. Clean the pepper and cut into strips. Thaw the peas.
Heat the oil, briefly fry the vegetables in it, remove from the pan. Add the liver and fry all over for 10 minutes. Add the vegetables again. Mix the soy sauce, sherry and 2 tablespoons of water with the starch and pour into the pan. Bring to the boil briefly, toss and season with salt and pepper.