Bring vinegar to a boil in small non-reactive saucepan. Cook over medium heat 20 minutes or until reduced to 1/4 cup.
Mix butter and flour in small bowl until smooth; set aside.
Add broth, reserved drippings and pepper to saucepan. Gradually whisk in butter mixture until smooth; bring to a boil. Reduce heat; simmer 1 minute, stirring constantly. Keep warm until ready to use.
Ingredients
1 cup beef broth, condensed
1/4 tsp black pepper, table grind, coarse grind
1/4 cup Nature's Best Dairy® Butter, Unsalted, softened