Hollandaise Sauce
About 1 Cup

Melt slowly and keep warm: ½ cup butter
Barely heat: 1 ½ tablespoons lemon juice, dry sherry or tarragon vinegar
Have ready a small saucepan of boiling water and a tablespoon with which to measure it when ready. Place in the top of a double boiler – over-not-in-hot water: 3 egg yolks
Beat the yolks with a wire whisk until they begin to thicken. Add:1 tablespoon boiling water
Beat again until the eggs begin to thicken. Repeat this process until you have added: 3 more tablespoons water.
Then beat in the warm lemon juice. Remove double boiler from heat. Beat the sauce well with a wire whisk. Continue to beat while slowly adding the melted butter and:
¼ teaspoon salt
A few grains cayenne
Beat until the sauce is thick. Serve at once