- 1 stick (1/2 cup) unsalted butter
- 2 tablespoons dry white wine
- 2 tablespoons white-wine vinegar
- 1 tablespoon chopped shallot
- 3 tablespoons heavy cream
- a few drops fresh lemon juice
- Cut butter into small pieces and chill. In a small heavy saucepan simmer wine, vinegar, and shallot over moderate heat until liquid is reduced to about 1 tablespoon, about 5 minutes. Add cream and simmer mixture until slightly thickened, about 2 minutes. Gradually add butter a few pieces at a time, whisking and adding more before previous pieces are fully incorporated (mixture will be creamy and pale). Remove pan from heat and pour sauce through a fine sieve into a sauceboat, pressing on solids. Season sauce with lemon juice and salt and pepper.
- Serve sauce immediately.