Preheat oven to 430°F.
In a small bowl, mix together sugar, melted butter, truffle oil, and white wine vinegar. Keep aside.
Remove chicken from the brine solution and pat dry with paper towels.
Loosen skin on the breast with a dessert spoon. Pour in the truffle oil mixture underneath the skin, and spread it by rubbing over the skin with the spoon.
Coat the chicken with the remaining truffle oil mixture using a basting brush. Or pour the truffle oil mixture over the chicken and spread evenly.
Place the chicken on a rack in a roasting pan, or elevate the chicken using carrots or onion placed in the roasting pan.
Stuff the chicken cavity with a few sprigs of thyme. Tuck wings under the sides of the chicken and tie the legs together with a string.
Pour 1 cup of low sodium chicken stock / dry white wine / Cognac into the roasting pan.
Turn down the heat of oven to 350°F and roast the chicken for approximately 1 hour or until a thermometer inserted into the thickest part of the chicken thigh reads 165°F.
If you'd like the skin to be crispier or more brown, broil for another 3 - 5 minutes. (I don't always broil.)
Remove from oven and let the chicken rest for 10 - 15 minutes before carving. Serve with pan drippings.