1 tablespoon butter
4 mushrooms, sliced
1 clove garlic, minced
2 tablespoons whole black peppercorns
1/4 cup Merlot wine
1 tablespoon balsamic vinegar
3 tablespoons Worcestershire sauce
1/2 teaspoon minced fresh rosemary
Melt butter in a saucepan over medium heat. Stir in the mushrooms, garlic, and peppercorns, and saute until the mushrooms are tender.
Pour in the wine, balsamic, and Worcestershire sauce, increase the heat to medium-high, and reduce by 1/3.
Stir in the rosemary and cook for 1 to 2 minutes until fragrant.