Juice of 1/2 lemon Salt to taste Pinch of cayenne Melt the butter and keep it hot, but do not brown. Put the yolks, lemon juice, salt and cayenne in the container of en electric blender. Blend on low speed, gradually adding the hot butter until the sauce is thickened and smooth. About 3/4 cup. The New New York Times Cookbook, by Craig Claiborne with Pierre Franey, Times Books, NY, 1975.