Hollandaise is notoriously tricky - ask anyone. The preparation is classic, and there are a lot of rules to making it. Professional chefs around the world tout the classic method of making this sauce: the double boiler method. This is how I was taught to make Hollandaise in college (big shout out to my instructor, Linda Kinney, but by no means is this a direct quote):
"Reduce vinegar (or lemon juice) with a few peppercorns in a double boiler over low simmering water. Remove the peppercorns and add in your egg yolks. Whisk like mad until they double in volume, but be careful not to over heat and scramble your yolks. Then remove your bowl, put it on a towel wrapped in a circle to insulate the bowl and keep it steady while you whisk like mad again as you pour hot melted butter into your yolks. Make sure there are no open windows or drafts, because this will break your sauce."
And break it did. My cooking partner and I totally forgot to close the window (mostly because I thought that the warning was crap), and our sauce... well, it went to that great Sauce Pot in the sky. Alas. The fun part was, since we had time left in class, we got to start all over again, only this time, we had to get it right.
