Oven-baked chicken with shallots and rosemary sauce

Ingredients:

• 2 bone-in, skin-on chicken breasts, halved (about 300g each)
• 3 tbsp (45 g) butter
• 4 medium shallots, peeled and quartered lengthwise (about 240g)
• 2 sprigs of fresh rosemary
• 3/4 cup chicken broth + 0.5 cup as needed

Preparation:

1. Preheat oven to 220°C.
2. Season the chicken breasts with salt and pepper on both sides.
   
   Heat a large skillet over medium-high heat for 2 minutes. Working quickly, melt 1 tablespoon (15 g) butter, shaking the pan. Place the chicken skin-side down. Add the shallots, cut side down, making sure not to overlap the slices. Cook until the chicken and onions are golden brown on the bottom, 2 to 3 minutes. Turn the shallots and chicken over, arrange the rosemary sprigs, then carefully pour in the chicken broth.
3. Place the skillet in the oven and bake until the chicken is cooked through and the shallots are tender, 12 to 14 minutes, removing the smaller chicken pieces first when they are done. Transfer the chicken to a plate.
4. Be careful not to let the broth evaporate in the pan with the onions; if there's less than a couple of tablespoons left, add another 1/2 cup of broth or water. Place the pan over medium heat and reduce the liquid to about 1/2 cup, about 2 minutes. Remove the pan from the heat and stir in the remaining 2 tablespoons (30 g) of butter with a wooden spoon to thicken the sauce until it coats the spoon. Remove the rosemary and season the sauce with salt and pepper.
   
   Drizzle some of the sauce over the chicken and onions and transfer the rest to a plate.