Created by Sue on May 6, 2013
Step 1: In the top of a double boiler with simmering water below, whisk the yolks, lemon juice, and mustard until thoroughly combined.
Step 2: Add the melted butter in a thin stream, whisking constantly, until it is just thick enough that your whisk leaves a little bit of a trail. This should only take a couple of minutes.
Step 3: Whisk in the cayenne/sauce and season to taste with salt.
Step 4: If the sauce is too thick or tries to break, try adding hot boiling water a few drops at a time to bring it back together. Also, make the sauce as close as possible to the time you will serve it, as it doesn't hold very well.