Combine cider vinegar, cider, brown sugar, mustard seed, Dijon, tomato paste, salt, pepper, and neck bones in a heavy bottomed saucepan over medium heat. Simmer until sauce thickens, 30 to 40 minutes. Skim any foam from the surface of the liquid and discard. Remove and discard neck bones. Use immediately or cool to room temperature.
Carolina BBQ Sauce · Dinner Match Lab | Dinner Match Lab