Melt 2 T margarine in a small saucepan. Mix together and stir in
    1/4 cup unsweetened cocoa and 1/2 cup sugar; add 1/4 t. vanilla
    and 2 T water. Stir over high heat until smooth and, when
    bubbling, cook and stir I minute more. Serve immediately. (This
    sauce is thin, but thickens when it touches the ice cream. It
    strings just a little, and you can lift it right off the ice
    cream. Very quick, easy and delicious) Source: Julia Child