- ½ cup balsamic vinegar
- 4 tablespoons extra-virgin olive oil
- 2 tablespoons maple syrup
- 3 garlic cloves minced
- ½ teaspoon kosher salt or more to taste
- ¼ teaspoon freshly ground black pepper or more to taste
- 6 chicken thighs
- 1 pound Brussels sprouts ends trimmed off and sliced in half
- 1 red onion sliced into wedges