In a shallow dish, combine all the marinade ingredients and add the cubed caribou. Cover and leave in a cool place for 24 hours. Remove the meat cubes from the marinade. Pat dry and roll in a little flour. Strain the marinade and reserve.
Cut the peppers in half and remove seeds. Chop the peppers into cubes. Chop the onion and mince the garlic. Cut the celery into 1 cm slices. Heat the oil in a large frying pan, and brown the caribou quickly. Remove it, then add the chopped vegetables to the oil and saute quickly; but do not allow to brown.
Put the caribou and fried vegetables into a flameproof casserole. Add the tomatoes, roughly chopped, and the tomato paste.
Sprinkle the paprika, caraway seeds, and salt and pepper to taste on to the contents of the casserole, and pour in the marinade liquid. Stir well and bring almost to boiling. Cover. Turn down the heat and simmer gently on top of the stove for 1.5-2 hours.
25 minutes before the goulash is ready, add the potatoes, peeled and cubed.
Just before serving, add the yoghurt/sour cream and stir. Taste for seasoning: more paprika or caraway may be added if liked.