In a brining bucket or container large enough to hold the turkey inside the refrigerator, combine 1 cup salt, 1 cup packed brown sugar and 1 tablespoon black peppercorns. Add 6 quarts cold water and whisk until the salt and sugar are dissolved. Submerge one 12- to 14-pound turkey (neck and giblets removed and reserved, bird rinsed inside and out) into the brine; if the water does not cover the bird, add up to 2 quarts more water. Place a clean kitchen towel on top of the turkey and weigh down the turkey with a heavy plate to keep it submerged. Refrigerate the bucket overnight or up to 18 hours. One hour before cooking, remove the turkey from the brine and rinse well. Pat dry and let come to room temperature.