Step 1

Place wrapped turkey in a 5-gallon cooler with a drain spout. Place cooler in a bathtub and cover turkey with cold water. Drain and replace water every 2–3 hours, keeping water temperature below 40°, until turkey has thawed, 8–10 hours.

Step 2

Clean cooler with soap and water, then pour in hot tap water, salt, and sugar. Stir thoroughly to dissolve salt and sugar. Then stir in ice and vegetable broth.

Step 3

Unwrap thawed turkey and remove any parts (such as neck, organs, etc.) that may be inside cavity. These may be saved for gravy.

Step 4

Place turkey in brine breast side up. If turkey floats, fill a 1-gallon resealable plastic bag with water and place it on top of turkey. Set cooler, lid closed, in a cool place, turning turkey over once if possible, 8–12 hours. Check brining liquid periodically with probe thermometer; if temperature is above 40°, add a few freezer packs that have been enclosed in resealable plastic bags.

Step 5

Remove turkey from brine, rinse under cold water, and pat dry with paper towels. Do not stuff turkey.

Step 6

Remove all oven racks except for one. Set this rack in the next-to-the-lowest position. Preheat oven to 500°.

Step 7

Loosely pack turkey with a combination of herbs, carrots, celery, and onion. Keep packing loose.

Step 8

Place turkey, breast side up, on a V-shaped rack set inside a large roasting pan. Cut a piece of foil big enough to cover the turkey's breast. Mold piece to breast. Remove foil, then grease with spray.

Step 9

Rub butter between your hands until liberally greased (you may use disposable gloves if desired). Rub butter into turkey. You may need to re-butter your hands a couple times in order to get a nice, even coating.

Step 10

Place turkey in oven, neck end first and breast up. Roast turkey until nicely browned, 30–40 minutes. Apply foil to breast of turkey. Insert thermometer probe directly through foil into deepest part of breast.

Step 11

Reduce oven temperature to 350° and return turkey to oven, foil securely in place. Do not open oven to baste turkey. Roast until probe registers 161° for breast and 181° for thigh, 2–2½ hours.

Step 12

Cover turkey with foil and let rest 30 minutes. Save pan drippings for gravy.

Step 13

Carve turkey.

Step 14

Mix pan drippings with water, chicken broth, and cornstarch. Heat in a small saucepan over medium until thickened.