Rinse and Truss the Turkey Remove the neck and giblets from the turkey and reserve for another use. Rinse and dry the turkey inside and out. Set it in on a work surface or in a large baking pan. Sprinkle the cavity with salt and pepper and put 2 lemon slices and 3 garlic cloves in the cavity. Truss the legs of the turkey by cutting off a 12-18 inch piece of twine and tying the legs together (see photo on the blog).
Make the Marinade Spoon the Aleppo pepper (or the red pepper flakes and paprika) into a large bowl. Add 2 tablespoon of warm water (3 tablespoons, if using pepper and paprika) and stir to moisten the spices. Set aside for 5 minutes. Add the yogurt, tomato paste, olive oil and salt to the bowl. Mix gently with a fork, stirring only in one direction, until the ingredients are just combined. Add the remaining lemons and garlic to the bowl, and gently stir, in the same direction.
Coat the Turkey with Marinade Preheat the oven to 450ºF. Place the oven rack in the lowest position. Make sure the trussed turkey is in your roasting pan – breast side up. Pour the yogurt marinade over the top of the turkey. Lift the bird by the neck and, using your hands, smear some marinade over the bottom of your turkey. Pat marinade over the wings and legs and any areas that are bare. Let the turkey sit with the marinade at room temperature for 30-45 minutes. (Or you can marinate the turkey for up to 24 hours in the fridge).
Roast the Turkey Before cooking, mound excess marinade onto the turkey. Remove any garlic cloves from the top of the turkey to prevent them from burning, leaving them in the pan. Gently place some lemon slices around the top – decoratively, if you like. Roast the turkey at 450ºF for 30 minutes. Remove the pan from the oven and set it on a heat-proof surface. Gently pour the melted butter over the top of the turkey. Return the turkey to the oven. Lower the heat to 350ºF and roast the turkey for 2 – 2 1/2 hours longer, or until a meat thermometer inserted into the thickest part of the breast registers 161F – baste every half hour with pan juices – add a cup of stock to the pan when it looks dry – if any part of the turkey is getting too brown, press some foil over it.
Make the Gravy Transfer turkey to a platter and tent with foil while you make the gravy. Remove the roasted garlic and lemon slices from the roasting pan and set aside. Pour the liquids from pan into a gravy separator. (do not clean the roasting pan) Wait a few minutes until you see that the fat has risen to the top, then pour the liquid into a medium sized saucepan. Set the fat aside.
Set the roasting pan on the stove over two burners set to medium heat. Add a cup of stock to the pan and stir, scraping the bottom with a wooden, spoon to release all of the flavorful brown bits. Turn off the heat and pour liquid into the saucepan. Add the roasted garlic to the pan. I like to spoon in a couple of tablespoons of the fat for flavor – you can leave it out entirely for a non-fat gravy or add as much as you like for a richer gravy.
Puree the Gravy Puree the gravy with an immersion blender or in a blender or food processor. Return it to the pot (if you removed it) and thin with some broth until you get your desired consistency. Season with salt, to taste.
Slice turkey and serve it with spicy yogurt gravy.