- 3 egg yolks
- 1 Tablespoon fresh lemon juice
- ½ pound butter, melted
- 1 ½ Tablespoons boiling water
- Dash of Cayenne pepper
- Salt to taste
- 1 thin sliver of shallot (optional)
The shallot is something my mother always added – if you add a teaspoon of fresh tarragon you will have a Bearnaise sauce. If using unsalted butter be sure to adjust the seasoning carefully.
Put the egg yolks in a food processor with the shallot if you are using it. Turn the processor on – keep it on as you add all of the ingredients. Only turn it off when you are ready to taste and correct the seasoning. Make sure the onion is shredded before slowly adding the boiling water (if you just dump it in the eggs may scramble and you will have to start over).
Add the melted butter in a very thing stream. Add the lemon juice, Cayenne, and salt. Taste and correct the seasonings.
Keep warm over a double boiler (very low heat) until ready to use.
Make ahead: Transfer to a glass bowl and cover with plastic wrap pressed to the surface. Refrigerate until about an hour before you expect to use it, and then reheat either over a double boiler or in the microwave. If you use the microwave, heat the sauce for 1-2 minutes on medium low (power level 4) – stir it vigorously and keep heating it a for short times at low power until it’s properly warm. If you go too fast and it curdles you are sunk, so be patient.