Sauté the onion in the butter.
Put the cabbage whole in boiling water and let boil 10 minutes. Remove from water. Reserve liquid. Separate the leaves carefully.
Mix well the meats, rice, onion, salt and pepper to taste. Put 1 heaping tablespoon of the meat mixture on a bed of 2 or 3 leaves. Wrap and tie each roll well. Cook slowly in the water cabbage was cooked in.
When tender, coat the cabbage rolls in browned butter and serve hot.