Cut the meat into 2 cm pieces and roughly dice the onion. Heat the butter and oil in a deep pan and fry the meat in it. Roast the onions briefly, then add the stock and stew everything covered over medium heat for 10 minutes.
Peel the carrots and slice thinly. Peel and finely chop the ginger. Add both to the meat and simmer for another 10 minutes with the lid on. Mix the sour cream, curry and sherry and pour over the meat. Then let it boil down for another 5 minutes.
Toast the sesame seeds in a dry pan. Season the curry with salt and pepper and mix in the sesame seeds.