1 large whole skin-on, bone-in turkey breast (about 2.2kg)
Salt and pepper
Method
Carefully remove turkey skin in a single piece and set aside. Using a sharp boning knife, remove breast meat from breastbone. Set breastbone aside. Season turkey generously with salt and pepper on all sides. Place 1 breast half, cut side facing up, on a work surface. Place second breast half facedown, with the fat end aligning with the skinny end of the first breast half. Gently form into an even cylinder.
Tie turkey breast at 1-inch intervals using butcher's twine. Transfer to a zipper-lock bag. Turkey can be refrigerated for up to 5 days before proceeding.
Adjust a sous vide water bath to 145°F (63°C) or to desired temperature according to chart above. With bag open, slowly lower bagged turkey into water, letting water pressure squeeze air out of bag until just the seal remains above the waterline. Seal bag completely. Let turkey cook for 2 1/2 hours (or according to chart above). Meanwhile, make the crispy skin.
For the Crispy Skin: Adjust oven rack to center position and preheat oven to 400°F (204°C). Spread skin evenly over a piece of parchment paper set in a rimmed baking sheet. Season generously with salt and pepper. Place a second sheet of parchment on top and carefully squeeze out any air bubbles with the side of your hand. Place a second rimmed baking sheet on top and transfer to oven.
Roast until skin is deep brown and crisp (it will crisp further on cooling), 30 to 45 minutes. Allow to cool and set aside at room temperature. Turkey skin can be roasted in advance, cooled completely, then stored loosely covered at room temperature for up to 3 days. To re-crisp, place in a hot oven for a few minutes just before serving.
When turkey is cooked, remove from water bath and unseal bag. Carefully remove butcher's twine. Slice into 1/4- to 1/2-inch slices for serving. Fan slices out on a warmed serving platter or cutting board. Break skin into serving-sized pieces and add to platter along with a pitcher of gravy. Serve immediately.