In a large double boiler place all the ingredients. Allow ingredients to cook until completely melted and smooth. When smooth, put about 1 cup of the mixture at a time through a blender on high speed-using pulse-about 1 minute or until each cupful is satiny smooth. The mixture has a tendency to curdle as it is cooking, but this can be smoothed out with use of a blender. Store in a tight fitting jar and refrigerate to be used within a month. Freeze it to be used within 3 months.