- 1 tablespoon high-heat oil
- 1/2 red onion, minced
- 2 cloves garlic, minced
- 1/4 cup balsamic vinegar
- 3 tablespoons brown sugar
- 3 tablespoons molasses
- 2 tablespoons Dijon mustard
- 1 tablespoon instant coffee granules
- Pinch of red pepper flakes
- 1 pint blueberries
- 4 chicken thighs or drumsticks
- Salt and pepper, to taste
Heat oil in a saucepan over medium-high heat. Add onions and garlic and cook until soft, about 5 minutes. Stir in vinegar, brown sugar, molasses, mustard, coffee and red pepper flakes. Bring to a simmer, then stir in blueberries. Simmer until blueberries start to burst and sauce thickens slightly, about 10 minutes.
Let cool slightly then blend until smooth. Pass through a strainer and season with salt and pepper. Reserve half the sauce for serving. Place remaining sauce with chicken in a sealable plastic bag and let rest in the refrigerator for 30 minutes to 1 hour.
Preheat grill to medium heat. Lightly oil grill grates.
Season chicken liberally with salt and pepper. Grill until cooked through (the temperature taken with an instant-read thermometer should read 165° F), 7 to 10 minutes per side, depending on the thickness of the chicken. Serve with reserved sauce.