Béarnaise Sauce

In a small saucepan, combine vinegar, white wine, minced shallots, half the tarragon (roughly chopped, stems included), and cracked peppercorns. Bring to a boil, then reduce over medium heat until only about 2–3 tablespoons of liquid remain — the shallots should look almost jammy and the liquid should be syrupy and fragrant. Strain through a fine-mesh strainer, pressing on the solids. Reserve the strained shallots if you wish to stir them back in later (classic Béarnaise adds them back). Let the reduction cool to room temperature.

Gently melt the butter in a small saucepan over low heat without stirring. Skim the white foam from the surface. Carefully pour the clear golden liquid (clarified butter) into a warm jug, leaving the white milky solids behind. The butter should be warm (60–65 C) when you add it to the yolks — warm enough to emulsify, not so hot it scrambles the eggs. If using whole butter (unclarified), the sauce will have more flavor but slightly less stability.

In a round-bottomed stainless steel bowl (or the top of a double boiler), whisk together the strained reduction, egg yolks, and cold water until pale and slightly frothy. Place over a pot of barely simmering water (the bottom of the bowl must not touch the water). Whisk constantly and vigorously in a figure-eight pattern for 3–5 minutes, moving the bowl on and off the heat as needed, until the mixture has thickened to the consistency of lightly whipped cream — when you lift the whisk, a ribbon of yolk falls and holds on the surface for 3 seconds before dissolving.

Remove the bowl from the heat. Begin adding the warm clarified butter in a very thin, steady stream while whisking constantly — almost drop by drop for the first 50 ml. As the emulsion establishes, you can increase to a thin drizzle. If the sauce thickens too much and looks greasy, add a teaspoon of warm water and whisk to loosen. Once all butter is incorporated, stir in the remaining fresh tarragon (finely chopped), season with salt and a few drops of lemon juice. Serve immediately or keep warm in the bain marie (no higher than 55 C).