Melt 2 Tbs. of the butter in a large sauté pan over medium-low heat. Cook the shallots, stirring occasionally, until they’re soft and translucent, 10 to 12 minutes. Turn the heat to high, add the wine and vinegar, and boil until reduced to a syrupy consistency (about 1/4 cup), about 10 minutes. Add the thyme and the beef broth and reduce to 1 cup, about 20 minutes. Strain the sauce, let cool, cover, and refrigerate.
Just before serving, reheat the sauce in a saucepan over medium heat. When it's hot, whisk in the remaining 3 Tbs. of butter.
nutrition information (per serving):
based on eight servings;
Photo: Scott Phillips