Peel the onion and chop finely. Steam the onion cubes in the oil until translucent (do not brown!). Pour off the oil. Mix the sour cream (possibly with a little water or sweet cream) until creamy. Put the onion cubes in the sour cream. Season to taste with salt, cayenne pepper and mild paprika powder.
Cut the cheese into cubes and cover with the sour cream. Let the whole thing stand in the refrigerator for about 1-2 hours (the longer the hotter it will be). Fresh farmer`s bread with butter and a cool blond also go well with this.