Melt 1 1/2 sticks of butter.
Have 2 sep arate tablespoons of cold butter on the counter.
In a heavy saucepan, beat the egg yolks with a wire whisk until slightly thickened.
Add the water, lemon juice, salt and cay enne pepper.
Put the pan on a gentle heat and add the first tablespoon of cold butter.
Stir rapidly with a wire whisk.
Allow the butter to melt but not completely disappear, then add the second tablespoon of cold but ter.
When the butter has almost melted, re move the pan from the heat.
Gradually add the hot butter, still stirring rapidly and con stantly.
The egg yolks will combine with the hot butter and thicken off the heat into a beautiful smooth sauce.
Check the seasoning, adding more lemon juice or salt if necessary.