Ingredients
3 bone-in, skin-on chicken-breast halves (about 2 pounds total), room temperature
Kosher salt and freshly ground pepper
2 tablespoons unsalted butter
3 tablespoons extra-virgin olive oil
3 medium leeks, white and light-green parts only, cut into 1-inch rounds, then thoroughly washed and drained (2 cups)
5 medium carrots, peeled and cut on the bias into 1 1/2-inch pieces (2 cups)
2 cups Italian-bread cubes (each about 1 inch square; from 1 small loaf)
2 cloves garlic, minced (2 teaspoons)
1 teaspoon grated lemon zest, plus 3 tablespoons fresh juice
1/4 cup lightly packed fresh mint leaves, sliced, plus more for serving
Preparation
Preheat oven to 450°F. Pat chicken dry; season generously with salt and pepper. Heat a large, heavy ovenproof skillet (such as cast iron) over medium-high. Add butter and 1 tablespoon oil. When butter melts and foam subsides, add chicken, skin-sides down. Cook, undisturbed, until skin lifts easily from skillet and forms a golden-brown crust, about 5 minutes. Transfer to a plate, skin-sides up.
Add leeks, carrots, bread cubes, garlic, lemon zest, and remaining 2 tablespoons oil to skillet, stirring to evenly coat; season with salt and pepper. Return chicken and any accumulated juices to skillet, arranging breasts on top of vegetables in a single layer, skin-sides up.
Roast until a thermometer inserted into thickest part of breasts reads 160°F, 25 to 30 minutes. Transfer chicken to a plate and loosely cover to keep warm. Stir mint into skillet; return to oven. Roast until vegetables are tender and golden and bread turns crisp, 10 to 12 minutes. Stir 1 1/2 tablespoons lemon juice into vegetable mixture and sprinkle with more mint leaves. Drizzle remaining 1 1/2 tablespoons lemon juice over rested chicken. Carve chicken; serve with vegetable mixture.
