Sauce Béarnaise

The emulsified sauce base that is prepared here is used for all of the sauces that follow; the flavor reduction of herbs, vinegar, white wine, and shallots makes this sauce specifically a sauce béarnaise. Traditional recipes for sauce béarnaise call for chervil in the flavor reduction, but in this recipe it is optional. The flavor of tarragon is so much more assertive that the flavor of the chervil is usually overpowered and lost. While the traditional approach is to prepare the reduction o