After searing meat, add butter to the hot pan over medium heat.
Add rosemary and garlic and cook 30 seconds or just until fragrant.
Stir in the red wine and cook until reduced by half scraping up any brown bits in the pan.
Stir in broth & vinegar, bring to a boil, reduce heat to a simmer and let cook until reduced and slightly thickened.
Season with salt & pepper to taste, serve sauce over meat.
