In a stainless steel bowl set over a pot of simmering water, whisk the egg yolks with the lemon juice, hot pepper sauce, and water, until pale yellow in color. Season with salt and pepper. Be careful not to let the bowl touch the water. Remove the bowl from the pot and whisking vigorously, add the butter, 1 teaspoon at a time, until all is incorporated. Fold in the whipped cream.
This recipe yields about 1 1/4 cups of sauce.