Step 1

Heat the oven to 450°F with a rack in the middle position. If the chicken breasts are larger than about 12 ounces each, cut them in half crosswise. Season the chicken all over with salt and pepper.

Step 2

In a 12-inch oven-safe skillet over medium-high, heat the oil until shimmering. Add the chicken skin-side down and cook until golden brown on both sides, 8 to 10 minutes, flipping the pieces halfway through. Transfer to a large plate; set aside.

Step 3

To the skillet over medium, add the anchovies, garlic, rosemary sprigs and pepper flakes. Cook, stirring, until the anchovies have broken down and the mixture is fragrant, about 1 minute. Reduce to low, then slowly add the wine. Bring to a simmer over medium-high and cook, scraping up the browned bits, until the wine has reduced by about half, 8 to 10 minutes.

Step 4

Return the chicken skin-side up to the pan and add the accumulated juices. Transfer to the oven and cook until a skewer inserted into the thickest part of the chicken meets no resistance, 12 to 15 minutes.

Step 5

Remove the skillet from the oven (the handle will be hot) and set it on the stovetop. Transfer the chicken, skin side up, to a deep platter. Remove and discard the rosemary sprigs from the skillet. Add the minced rosemary and vinegar to the liquid in the skillet; bring to a simmer over medium-high. Cook, stirring, until reduced by about half, about 5 minutes. Remove from the heat, then taste and season with salt and black pepper. Spoon the sauce over and around the chicken.