In a saucepan pour the vinegar, add chopped in large pieces pepper and chopped onion. Allow the fire, while the vinegar almost turn aside. At this point, add the cream and egg yolks. The mixture was stirred on fire until a light cream. Remove from heat, without interrupting the stirring and gradually added prior macerate butter. Add salt to taste and lemon juice. The sauce was ground through a sieve to remove pieces of onion and pepper. Should be relatively thick and slightly sour. Very suitable for baked zander.