Roughly chop the onion and then sweat it in the butter in a large pan. Then add the tomato paste and roast briefly. Deglaze with a generous dash of wine and bring to the boil briefly. Stir in the cream and yoghurt, add the mushrooms (with the stock) and ketchup, season with cumin, cayenne pepper and coriander, stir everything well and set aside.
Cook the pasta until al dente according to the instructions on the packet.
Meanwhile, cut the leftover grilled meat into bite-sized pieces. Then grease a casserole dish of a suitable size with the butter. Mix all ingredients, add, cover with grated cheese and bake for 30 minutes at 180 ° C.