Make the marinade: In a large bowl, whisk balsamic vinegar, olive oil, honey, Dijon, garlic, herbs, salt, pepper, and red pepper flakes. Taste and adjust sweetness or salt.
Prep the chicken: Pat the chicken dry.
Add to the bowl and toss until well coated. Marinate at least 20 minutes, or up to 24 hours in the fridge for deeper flavor.
Heat the oven: Preheat to 425°F (220°C). Line a rimmed sheet pan with parchment for easy cleanup, or use a lightly oiled pan for best browning.
Prep the veggies: Toss your vegetables with a spoonful of the marinade or a drizzle of olive oil plus a pinch of salt and pepper.
Keep water-heavy veggies like tomatoes and green beans separate for now.
Load the pan: Spread sturdier veggies (potatoes, carrots, brussels sprouts, onions) in an even layer. Nestle the chicken pieces among them, skin-side up if using skin-on. Brush with any extra marinade from the bowl.
Roast the first round: Bake for 20 minutes.
Rotate the pan if your oven runs hot on one side.
Add tender veggies: Scatter quick-cooking veggies (peppers, tomatoes, green beans) around the chicken. Spoon any juices from the pan over the chicken.
Finish roasting: Continue roasting 15–20 minutes, until the chicken reaches 165°F internally and the vegetables are caramelized at the edges. If you want extra color, broil for 2–3 minutes at the end.
Rest and finish: Let the chicken rest 5 minutes.
Garnish with chopped parsley and a squeeze of lemon. Taste and adjust salt right before serving.
Serve: Plate with the roasted vegetables and pan juices. Add a simple side like quinoa, rice, or crusty bread to catch the glaze.