Salt and pepper liver. Saute over medium to high heat in the margarine (oleo). Remove liver and keep warm. Pour off some of melted oleo. In what is left, saute shallots until clear or tender. Add white wine. Bring to boil. Add mustard and blend into mixture. Stir and simmer for a few minutes.
Put liver on platter and pour sauce over it.
From Justin Wilson's "Outdoor Cooking with Inside Help"