Rub an oven-safe (and broiler-safe) casserole or serving dish with softened butter.
Arrange sliced turkey in prepared dish. Leave the skin facing up so that it can be easily crisped under the broiler.
(You can serve the turkey right out of this dish if you’d like, so take the time to make it look the way you would like it to look when served.) Cover the turkey tightly with foil and refrigerate for up to 24 hours.
When ready to serve, preheat oven to 350°F / 177°C.
Tip: Just before reheating, you can lift the foil cover off the turkey and taste the sliced breast meat. If the meat tastes bland or under seasoned, this is a great opportunity to add a bit more flavor. Lightly season the turkey with kosher salt, lifting the pieces up and seasoning underneath if you’d like to insure that everything gets seasoned. This is optional, but it’s a great opportunity to boost the flavor.
Pour chicken stock around sliced turkey, making sure to avoid any skin that you will want to get crisp under the broiler.
If you want to add some lemon juice to the turkey (see note below), slice a lemon in half and nestle it, cut-side up next to turkey slices.
Reseal the foil over the dish and bake until the turkey is just warmed through, about 15 to 20 minutes (it will continue to warm up under the broiler).
Remove the foil from the baking dish and turn on the oven’s broiler.
Slide turkey under the broiler. Keep a close eye on it and broil until the skin is deep golden brown and crisp, 3 to 4 minutes.
If using, lightly squeeze some juice from the lemon over turkey.
Serve warm.