01 - Preheat your oven to 425°F (220°C). Line a large rimmed baking sheet with parchment paper or aluminum foil for convenient cleanup.
02 - In a small bowl, vigorously whisk together the balsamic vinegar, maple syrup (or honey), olive oil, minced garlic, Dijon mustard, thyme, rosemary, salt, and pepper to create the marinade.
03 - Place the chicken thighs in a large bowl or a zip-top bag. Pour half of the prepared balsamic marinade over the chicken and toss to ensure all pieces are evenly coated. Allow to marinate for a minimum of 10 minutes, or for enhanced flavor, refrigerate for up to overnight.
04 - On the prepared baking sheet, arrange the halved Brussels sprouts, red onion wedges, and pitted cherries. Drizzle with the remaining half of the marinade and toss gently to coat uniformly.
05 - Nestle the marinated chicken thighs, skin-side up, amongst the arranged vegetables and cherries on the baking sheet. For extra flavor, brush with a small amount of additional marinade.
06 - Roast in the preheated oven for 30–35 minutes. The chicken is cooked through when it reaches an internal temperature of 165°F (74°C), and the Brussels sprouts should be tender and caramelized.
07 - For exceptionally crispy chicken skin, you may broil the sheet pan for an additional 2 minutes during the final stages of cooking.
08 - Remove the baking sheet from the oven and allow the chicken and vegetables to rest for 5 minutes. Before serving, garnish generously with chopped fresh parsley.