1. Place Roasted Chicken Stock in a small saucepan over medium-high heat; bring to a boil. Cook until reduced to 1/2 cup (about 20 minutes). Place stock in a bowl; keep warm.
2. Combine wine and next 3 ingredients (through thyme) in pan over medium-high heat; bring to a boil. Cook until reduced to 1/3 cup (about 8 minutes). Stir in reserved stock; return mixture to a boil. Cook until reduced to 2/3 cup (about 7 minutes). Strain mixture through a sieve over a bowl; discard solids. Stir in butter, 1 teaspoon at a time, stirring until butter melts. Stir in salt and pepper.