- Preheat oven to 375°F. Pat the chicken dry using paper towels and place it onto a cutting board breast side down. Using a pair of heavy duty kitchen shears remove the backbone by cutting down both sides of it. Discard the backbone or save it to make stock at a later date. Flip the chicken over and, using the palm of your hand, press between the breasts to flatten out the chicken.
- Heat a large cast iron skillet over medium-high heat. Drizzle the chicken with a bit of olive oil and generously season with salt and pepper on both sides. When the pan is hot, place the chicken breast side down and allow it to sear for 3-5 minutes until the skin begins to crisp and easily releases from the pan. Flip the chicken over and sear an additional 2-3 minutes before removing from pan.
- Turn the heat down to medium-low and deglaze the pan by adding in the chicken stock. Bring to a boil and add the butter and Roasted Apple Grille Sauce. Bring back to a boil and continue to stir until it has thickened and reduced slightly. Turn the heat off and remove the sauce from the skillet.
- Arrange the apples, onions and garlic cloves amongst the bottom of the skillet and scatter the thyme sprigs on top. Place the seared chicken, breast side up, on top of the apples and onions. Glaze the chicken with the sauce and place the skillet in the oven, uncovered for 50-60 minutes or until internal temperature reaches 165° in the breast and 175° in the thigh.
- Remove the chicken from the oven and allow to rest for 10 minutes before serving.