Crispy Chicken and Potatoes with Mustard
1 whole chicken, about 4 pounds, quartered
2 tablespoons unsalted butter, room temperature
3 tablespoons grainy mustard
1 tablespoon chopped fresh rosemary
1 tablespoon chopped capers
3 tablespoons olive oil
1 1/2 pounds small roasting potatoes or larger potatoes cut into 1 ½-inch chunks
Kosher salt and freshly ground pepper
Preheat an oven to 400F.
In a small bowl, combine the butter, mustard, rosemary and capers. Loosen the skin of the chicken by gently sliding your fingers between the skin and the meat. Rub the mustard–herb mixture beneath the skin. Coat the outside of the chicken with 1 tablespoon of the olive oil and season with salt and pepper.
Wash and dry the potatoes. Place them in a single layer in a roasting pan. Drizzle with the remaining 2 tablespoons of olive oil and season generously with salt and pepper. Place the chicken pieces on top the potatoes. Roast for 50-60 minutes.
Remove the chicken from the pan and temporarily set it on a platter. Toss the potatoes. Place the chicken back on top of the potatoes and continue to roast the chicken until the thickest part of the chicken registers 165 degrees on an instant-read meat thermometer.
Transfer the chicken to a platter and serve alongside the potatoes.