Lemon-Rosemary Chicken with Roasted Broccolini
- Preheat oven to 425 degrees F.
- Combine parsley, rosemary, garlic, Dijon, and 1 tablespoon oil in a bowl. Season with salt and black pepper. Place 8 lemon slices and half of rosemary mixture underneath skin of chicken, dividing evenly. Rub remaining rosemary mixture over chicken, dividing evenly. Roast, on a rimmed baking sheet, 20 to 22 minutes.
- Meanwhile, toss Broccolini, onion, red pepper, remaining lemon slices, and remaining 2 tablespoons oil in a bowl. Season with salt and black pepper. Remove baking sheet from oven and arrange vegetables around chicken. Bake until an instant-read thermometer inserted in the thickest portion of the chicken reaches 165 degrees F, 12 to 14 minutes.
- Serve with red pepper for sprinkling.