Wash the fillet, dab dry and dice. Marinate in the soy sauce for about 30 minutes. Clean, wash and dice the potatoes, carrots and courgettes. Chop the pineapple. Dust the fillet with starch.
Heat the oil in a pan. Brown the meat in it and take it out. Brown the potatoes and carrots in the frying fat, deglaze with sherry and broth and steam covered for about 5 minutes. Add seasoning and pineapple.
Steam for another 5 minutes. Add meat and zucchini. Steam for another 5-10 minutes. Season with salt, pepper and sesame oil.