One Egg Hollandaise - paraphrased from recipe posted by Chowhounder RelishPDX in April 2014
1 egg yolk from a large egg
1/4 egg white from the egg (whisk egg white lightly to break it up, if necessary) - you may use all the egg white if you’re good with the whisk while cooking, but risk getting “scrambled eggs” not sauce…
1/3 stick (2 T plus 2 tsp) of salted butter at room temperature (or add a dash of salt to unsalted)
1 Tbsp lemon juice
Place all of the ingredients at the same time into a 2-qt. Pyrex casserole dish (or metal top pan of a double boiler), sitting over a 1-1/2 qt. saucepan half-filled with hot water (water should not touch the bottom of the top dish) . Turn the burner up to HI, and begin to slowly whisk ingredients together. Once the water in the pan sounds like it’s about to boil, turn the burner off. Continue whisking until the mixture thickens, lifting the casserole dish /double boiler pan off of the saucepan once the sauce is finished.
This sauce holds very well and makes just the right amount for a meal (or breakfast) for two. If any is leftover, refrigerate and it may be reheated in the microwave briefly on a low setting stirring occasionally.
