Preheat oven to 400°.
Combine first 5 ingredients in a small bowl. Loosen skin from turkey by inserting one hand, palm side down. Gently push hand beneath the skin and against the meat to loosen skin. Rub thyme mixture over turkey. Press skin to secure.
Place breast half, skin side up, on a broiler pan coated with cooking spray. Insert meat thermometer into meaty part of breast, making sure not to touch bone. Bake at 400° for 1 1/2 hours or until meat thermometer registers 180°. Let stand 10 minutes. Remove skin, and discard. Cut breast into thin slices; garnish with thyme sprigs, if desired.
Little-known fact: Thyme was once said to be an antidote for shyness and nightmares.