Set a glass or metal bowl over a pot of gently simmering water (do not let the water touch the bowl).
Add egg yolks to bowl. Using a metal whisk or wire whip, whisk the yolks constantly without overcooking the yolks. You'll know the yolks have thickened enough when you can draw a line through the yolks and yolks stay put. The line does not fill in.
Remove from heat and immediately stir in lemon juice. Off the heat, set a kitchen towel over pot of water and set bowl on top.
Starting with just a few drops at a time, whisk in the warmed clarified butter. Once the emulsion has formed, you can add butter more quickly.
Once all the butter has been added, taste for seasonings. Add salt and tabasco or cayenne pepper if desired.
Use immediately or set aside in a warm (but not hot) place for up to 1 hour. If the sauce appears to thick, whisk in a few drops of warm water until desired consistency is reached.
Clarified butter: To clarify butter, melt the butter over low heat (do not boil). Skim off the foamy milk solids that rise to the top. Ladle the remaining butterfat from the saucepan in to a second (clean) saucepan or another vessel for holding. Be sure to leave the water in the bottom of the original saucepan (it will look like a white, milky substance).
Yield: This recipe makes 12 ounces hollandaise sauce, enough for 4 (3-ounce) servings (enough to make 2 Eggs Benedict stacks per person).
Make ahead: The Hollandaise sauce can be made up to 1 hour in advance. Keep in a warm (but not hot) place.
Grainy or curdled: It probably got too hot. Try pulling it off the double-boiler immediately to cool it down or stir in a small amount of cool water
Emulsion isn't forming: The yolks might be too hot or too cold, the butter might be too hot or too cold, you added too much butter too fast, or didn’t whisk quickly enough.
Pale pink yolks: You may have left the whites in with the yolks.
Breaking: If your Hollandaise was perfect, but now it's breaking, it may have gotten too hot.