Rinse chicken and pat dry. Remove and discard neck and giblets. Trim any excess fat. Loosen skin from breast and drumsticks. Place minced garlic and rosemary beneath skin. Lift wing tips up and over back; tuck under chicken. Place chicken breast side up, on a broiler pan. Cut thin slice from end of each onion and peel. Cut tops off garlic, leaving root intact. Brush onions and garlic with olive oil; place around chicken. Bake at 450 degrees for 30 minutes. Reduce heat to 350 degrees and bake an additional 1 hour and 15 minutes or until meat thermometer registers 180 degrees. Yield: 8 servings.