[Editor's note: We trust you. We know you read carefully. But in response to some of the concerns on Facebook and in the comments section of this page, Andrew Schloss added the following introductory note in November 2015:
All of the harmful bacteria on a whole turkey is on its surface and an initial hour of high temperature roasting ensures that all of it will have bit the dust long before you reduce your oven temperature for slow roasting. Given that hour your bird will be perfectly safe, but if you should, say, skip the first hour and go directly to 170 degrees, or start with a still frozen turkey, or stuff your turkey before it roasts all bets are off. Any of these practices will encourage bacteria growth. THEY ARE DANGEROUS AND SHOULD BE AVOIDED AT ALL COSTS. Follow the directions below and I guarantee not just amazing succulence but pristine food safety. And if perchance you have one of those fascist ovens that turns itself off after 8 hours, you're going to have to stand guard and turn it back on. The fight against fascism takes constant vigilance! What can I say?]
I thought my recipe for Holiday Turkey [from the book Cooking Slow] was complete perfection, until I was asked to slow-roast a 20-pounder for a turkey promotion at our local co-op. Of course, I didn't follow my original recipe exactly (I am incapable of precise reproduction) and, damn, if it wasn't improved.
When I originally published the recipe, I was worried that your oven would not be quite up to temp, so I hedged my bets by recommending that you roast at 175°F, even though turkey meat is done at 170°F. I just wasn't ready to be deluged with letters blaming me for shocking pink thigh meat. Well, after consuming more than my share of this slow-roasted wonder, I can report that roasting at 170°F yields thorough cooking and incredibly succulent and moist meat throughout the bird with hardly any work on your part.
Like all slow-roasting, the method is a snap and life-altering. You will start up to 2 days ahead, but there is less than 15 minutes of labor in that entire 48 hours. Always start with a fresh or thoroughly thawed turkey, never stuff the bird, and use an oven thermometer to make sure your oven is correctly calibrated. Then settle down for a good night's sleep while the turkey's roasting. Here's the timeline for a 15- to 25-pounder:
Seasoned turkey after 24 hours in the refrigerator. (Photo: Andrew Schloss)
36 to 48 hours ahead: Season the turkey inside and out with salt and pepper and set on a rack in a roasting pan in the refrigerator, uncovered, for 12 to 24 hours. It is important to keep the turkey uncovered to allow the skin to dry. This will ensure that it crisps well during roasting. Don't worry: It won't make your refrigerator smell like turkey, nor your turkey like your refrigerator.
15 to 25 hours ahead (depending on the weight of the turkey): Remove the turkey (still on its rack, in its pan) from the refrigerator, drizzle it with oil, and roast at 450°F for 45 minutes to 1 hour. The skin will be burnished golden brown and any harmful bacteria that were occupying the surface will be eliminated. It is now safe to turn the temperature down and start slow-roasting for real.
Browned turkey after 45 minutes in 450 oven. (Photo: Andrew Schloss)
14 to 24 hours ahead (depending on the size of your turkey): Pour a quart of good-quality apple cider over the turkey, and season the liquid in the pan with a few big pinches of high-class poultry seasoning. (I, of course, use Chef Salt Truffle Herb, a redolent mix of truffle salt, pinot fleur de sel, Halen Mon Gold flake salt, porcini powder, and herbs.)
Reduce the oven temperature to 170°F and roast your turkey for at least 1 hour per pound. Because the oven temperature is no hotter than you want the bird to be at perfect doneness, it cannot overcook. The 1-hour-per-pound guideline is to ensure that the entire bird gets heated through, but roasting longer will not be a problem.
Fully roasted 20-pound turkey. Roasted for 20 hours at 170°F. (Photo: Andrew Schloss)
Remove the turkey and place on a carving board. Skim the fat from the surface of the pan juices. Carve the turkey (no need for resting) and serve with its apple cider jus.
Andrew Schloss is a restaurateur; the author of 12 cookbooks; a writer whose articles have appeared in the Philadelphia Inquirer, The Washington Post, the San Francisco Chronicle, the Chicago Tribune, Bon Appetit and Family Circle; and president of product development company Culinary Generations, Inc. He is the former president of The International Association of Culinary Professionals and former director of the culinary curriculum for The Restaurant School in Philadelphia. His website is AndrewSchloss.com. His latest book is Cooking Slow: Recipes for Slowing Down and Cooking More.