Preheat the oven to 375°F convection. If you are using a conventional oven without convection, preheat it to 400°F. Grease a large baking pan or roasting pan with butter or non-stick spray.

Spatchcock the chicken. Place the chicken breast-side down on a cutting board with the backbone facing up. Using a sharp pair of kitchen shears, cut along one side of the backbone from the tail end toward the neck. Repeat on the other side and remove the backbone completely. Flip the chicken over so the breast is facing up, then press down firmly on the center of the breastbone with the palm of your hand until the chicken flattens out. Place the chicken skin-side up in the prepared baking dish or roasting pan.

Sprinkle the underside of the chicken with about ½ tablespoon salt. Flip the chicken skin-side up, rub the olive oil all over the skin, and season with another ½ tablespoon of salt.

Crush the peppercorns by placing them between two clean kitchen towels and lightly pounding them with a rolling pin or meat mallet. The peppercorns should be broken into small pieces, but not finely ground.

Add the crushed peppercorns, rosemary, garlic, shallots, and 1 teaspoon of salt to a medium bowl. Pour in the heavy whipping cream and whisk everything together. Set aside.

Place the chicken in the oven and roast skin-side up for 15 minutes. The skin should just begin to turn lightly golden.

Remove the chicken from the oven and pour the peppercorn cream mixture over and around the chicken. Pour the sherry cooking wine around the chicken and gently stir it into the cream sauce in the bottom of the pan.

While the chicken cooks baste it every 15 minutes by spooning the sauce over the chicken.

The chicken is done when the skin is golden, the sauce is hot and bubbling, and a meat thermometer inserted into the thickest part of the breast reaches 165°F.

Remove the chicken from the oven and let it rest for at least 10 minutes before cutting and serving with extra creamy peppercorn sauce spooned over the chicken before serving.