Preheat oven to 350°.
Remove and discard giblets and neck from chicken. Rinse chicken with cold water, and pat dry. Trim excess fat.
Rub chicken with tarragon, salt, and pepper. Place lemon in body cavity. Secure lemon in cavity with skewers or wooden picks.
Place chicken, breast side up, on a broiler pan coated with cooking spray. Insert meat thermometer into meaty part of thigh, making sure not to touch bone. Bake at 350° for 75 to 90 minutes or until meat thermometer registers 180°. Remove chicken from oven; cover with foil, and let stand 10 minutes. Discard skin and lemon.