Peel the onion and cut into fine strips. Cut the meat into cubes (or buy goulash directly). Sear the meat with the oil in a roasting pan on all sides.
Add onion and garlic, dust with paprika and cayenne pepper and stir-fry everything. Season with pepper, salt and caraway seeds. Deglaze with the red wine and the broth, stir in the tomato paste and cover everything and cook over a low heat for about 1 hour.
Wash the pepper and cut into narrow strips. Roughly chop the sauerkraut. Add the paprika strips and sauerkraut to the meat and cook gently for another 15 minutes. Season again to taste and refine the sauce with the sour cream (or crème fraîche).