
1 (14- to 16-pound) fresh or frozen turkey
4 teaspoons fine sea salt, divided
6 tablespoons salted butter, softened
1 tablespoon finely chopped fresh sage, plus 10 to 12 leaves
1½ teaspoons finely chopped fresh rosemary, plus 2 (6-inch) sprigs
1½ teaspoons finely chopped fresh thyme, plus 5 sprigs
1 teaspoon lemon zest
¼ teaspoon ground black pepper
Nonstick cooking spray
1 small yellow onion, cut into large chunks
6 large cloves garlic, peeled and halved
2 fresh bay leaves
2 to 4 cups turkey or chicken stock
Roasted garlic bulbs, for garnish
Champagne grapes, for garnish
Fresh herb sprigs, for garnish