1 (4-pound) whole chicken, preferably free-range and organic
8 tablespoons (1 stick) unsalted butter, cut into tablespoon pieces and softened
1 (2 1/2-ounce) Perigord truffle*
Kosher salt and freshly ground black pepper
Preheat oven to 450°F
Rinse chicken and pat dry inside and out with paper towels. Turn it breast side up and starting at the tail end of the chicken cavity, work your hands beneath the skin to separate the skin from the breast, up to the neck. Take care not to tear the skin. Work your hands to the top part of the wing bone and around the thighs and down the legs.
Make sure your hands and work surface are clean. Using a mandolin, shave the truffle as thinly as possible, reserving scraps of truffle for the herb salad.
Rub the softened butter beneath the skin all along the areas where you loosened the skin.
Gently layer the truffle slices beneath the skin of the chicken, lining the breast and reaching as far back to the legs as well.
Season the interior of the chicken cavity with salt and pepper. Rub the remaining butter on the exterior of the chicken taking care not to shift the truffle slices beneath the skin and generously salt and lightly pepper the outside of the bird.
To truss the chicken, fold back the chicken wings and tuck them beneath the body. Wrap a piece of butcher’s twine fully around the tail, pull the legs together and cross one over the other. Pull the twine up and over the legs, tying them tightly together.
Place chicken in roasting pan or on a baking sheet set over a rack. Roast in the oven until the skin is browned and crispy, for about 20-30 minutes for approximately 10 minutes before slicing.
Reduce the temperature to 350°F and cook until the meat at the thickest part of the breast is 150-155°F, about 20 to 25 minutes. If the legs are not cooked through, detach them from the body, and continue to cook them until they read 150-155°F.
Allow the chicken to rest for 20 minutes before slicing. To slice, remove the legs from the body, cutting through the natural lines of the bird where the joints meet. Remove the wings from the breast. Then cut down the backbone and remove a breast half in one big piece. Repeat with the remaining breast half. (Try to keep the skin crisp and intact.) Cut the breast into 1-inch slices. Separate the legs into drumstick and thigh.