12 tablespoons unsalted butter, melted and kept warm
2 tablespoons minced fresh tarragon
Salt, to taste
Directions
Place the lemon juice, vinegar and shallots in a medium, nonreactive bowl and allow to macerate for 10 minutes (the shallots should be soft). Add the egg yolks.
Bring the water to a simmer in a 2-quart saucepan. Place the bowl of egg yolks over the saucepan (to create a double boiler). Whisking constantly, add the melted butter into the yolk mixture, drop by drop, until it begins to thicken.
Remove the bowl from the heat and continue whisking in the remaining butter to make a smooth sauce. Whisk in the tarragon and season with salt. Serve with steak, artichokes or potatoes.