Preheat and prep: Heat the oven to 425°F (220°C). Line a large sheet pan with parchment for easy cleanup.
If using rice or quinoa, start cooking that now according to package directions.
Mix the spice rub: In a small bowl, combine smoked paprika, garlic powder, onion powder, chili powder, cumin, salt, and pepper.
Season the chicken: Pat chicken dry. Drizzle with 1 tablespoon olive oil and coat all sides with the spice rub. Set aside while you prep the veggies.
Prep the vegetables: Toss broccoli, bell peppers, red onion, and sweet potato with 1–2 tablespoons olive oil and a pinch of salt and pepper.
Spread them on the sheet pan in a single layer.
Add the chicken to the pan: Nestle the seasoned chicken among the vegetables, leaving a little space around each piece for even roasting.
Roast: Bake for 15 minutes. Meanwhile, stir the BBQ sauce with apple cider vinegar or lemon juice if you want a brighter flavor.
Glaze and finish: Remove the pan and brush chicken generously with BBQ sauce. Toss veggies lightly if they’re browning too fast.
Return to the oven for 8–12 minutes, until the chicken reaches an internal temp of 165°F (74°C).
Rest and slice: Transfer chicken to a cutting board and let it rest 5 minutes. Slice or cube. If using black beans and corn, warm them on the still-hot sheet pan for 3–4 minutes.
Assemble bowls: Divide the grain among 4 meal prep containers.
Top with roasted veggies and chicken. Spoon over a little extra BBQ sauce if you like. Finish with chopped cilantro and a squeeze of lime.
Cool before sealing: Let bowls cool to room temp (about 20–30 minutes) before sealing to prevent condensation.