- 2 tablespoons chopped shallots
- 4 sprigs fresh tarragon
- 1/4 cup dry white wine
- 1/4 cup dry vermouth
- 4 large egg yolks
- 1 cup melted clarified butter or 1 cup (2 sticks) melted unsalted butter
- 1 teaspoon fresh lemon juice
- 2 tablespoons chopped fresh tarragon leaves
- 1/2 teaspoon salt
- 1/8 teaspoon freshly ground white pepper
- Combine the shallots, tarragon sprigs, white wine, and vermouth in a small saucepan, bring to a boil, and cook until reduced to 4 teaspoons. Strain through a fine-mesh sieve and let cool.
- In the top of a double boiler, or in a metal bowl fitted over a pot of simmering water, whisk the egg yolks and reduced wine mixture until ribbons start to form when the whisk is lifted. Whisking constantly, drizzle in the melted butter, a bit at a time, until the mixture thickens.
- Remove from the heat, add the lemon juice, chopped tarragon, salt, and pepper and whisk to blend. Adjust the seasoning, to taste.
- Serve immediately or keep warm, covered, over a pot of simmering water, for 5 to 10 minutes. Whisk before serving.