No double boiler is needed for this recipe, using the blender to emulsify the ingredients means no chance of the sauce separating! Yeah! Finally! An easy hollandaise sauce that is healthy too!
In a blender or food processor, combine the egg yolks, mustard, lemon juice, Worchester sauce, cayenne pepper and salt. Blend for about 5 seconds.
Melt the butter slowly in a small pot. Do not let it boil. Set the blender on high speed, and pour the butter into the egg yolk mixture in a thin stream. It should thicken almost immediately. Serve immediately while warm.