Preheat and prep: Heat the oven to 400°F (205°C). Line a large sheet pan with parchment for easy cleanup.

Make the sauce: In a bowl, whisk honey, Dijon, whole-grain mustard, apple cider vinegar, olive oil, garlic, smoked paprika, 1 teaspoon salt, and 1/2 teaspoon black pepper. Taste and adjust—add a pinch of salt or a splash of vinegar if needed.

Butterfly or pound the chicken: For even cooking, slice thick breasts in half lengthwise or gently pound to about 3/4-inch thickness. Pat dry with paper towels.

Marinate briefly: Toss chicken with half the sauce and let sit 10–20 minutes while you prep veggies. Reserve the rest for brushing and drizzling later.

Prep the vegetables: Trim green beans (or cut broccoli into florets). Slice bell peppers and red onion into strips. Toss with a drizzle of olive oil, salt, and pepper.

Arrange on the pan: Spread veggies on the sheet pan. Place marinated chicken on top or alongside, leaving a little space between pieces.

Bake: Roast for 16–20 minutes, depending on thickness, until the chicken reaches an internal temp of 165°F (74°C). Stir veggies once halfway through for even browning.

Finish with sauce: Brush chicken with some of the reserved honey mustard in the last 2–3 minutes of baking. Do not use leftover marinade that touched raw chicken.

Rest and slice: Let chicken rest 5 minutes, then slice against the grain. Toss veggies with a squeeze of lemon if you like.

Build your boxes: Divide your carb base (rice, quinoa, or sweet potatoes) among 4–5 containers. Top with sliced chicken and veggies. Drizzle with the remaining clean sauce. Garnish with parsley or red pepper flakes.