Classic Hollandaise Sauce

1.First, clarify the butter: Melt the butter gently in a small saucepan over low heat. Once melted, skim off the white foam (milk solids) from the top. Carefully pour the clear yellow liquid (clarified butter) into a separate measuring cup, leaving the remaining milk solids at the bottom of the saucepan. Keep the clarified butter warm, but not hot.

2.Set up a double boiler (bain-marie): Fill a medium saucepan with about 5 cm of water and bring it to a simmer. Place a heatproof bowl (preferably stainless steel) over the saucepan, ensuring the bottom of the bowl does not touch the simmering water.

3.In the heatproof bowl, combine the egg yolks, lemon juice, salt, and cayenne pepper. Whisk vigorously and continuously until the mixture thickens, lightens in color, and doubles slightly in volume. This process, known as making a sabayon, should take 3 to 5 minutes. The mixture should be warm to the touch but not scrambled.

4.Remove the bowl from the heat (or keep it barely hovering over the water) and begin the emulsion process. Slowly, drop by drop at first, whisk the warm clarified butter into the egg mixture. As the sauce thickens, you can gradually increase the stream of butter, whisking constantly and rapidly.

5.If the sauce becomes too thick, whisk in the optional teaspoon of cold water to thin it slightly and help stabilize the emulsion. If the sauce breaks (separates), whisk a fresh egg yolk with a teaspoon of cold water in a clean bowl, then slowly whisk the broken sauce into this new mixture.

6.Taste the Hollandaise and adjust the seasoning with additional salt or lemon juice as needed. Serve immediately. If holding, keep the sauce in a warm (not hot) spot, such as the back of a turned-off stove, for no more than 30 minutes.