Heat oven to 450 degrees. Put the turkey on a stable cutting board breast side down and cut out the backbone. Turn the turkey over, and press on it to flatten. Put it, breast side up, in a roasting pan. Wings should partly cover breasts, and legs should protrude a bit.

Tuck garlic and thyme under the bird and in the nooks of the wings and legs. Using a pastry brush, brush melted butter all over, and sprinkle liberally with salt and pepper.

Roast for 20 minutes, undisturbed. Turkey should be browning. Remove from oven, baste with pan juices, and return to oven. Reduce heat to 400 degrees (if turkey browns too quickly, reduce temperature to 350 degrees).

Begin to check turkey's temperature about 20-30 minutes later. It is done when thigh meat registers 165 degrees on an instant-read meat thermometer. Check it in a couple of places.

Let turkey rest for a few minutes before carving, then serve with garlic cloves and pan juices.