1. To make the brine, dissolve the salt and sugar in large stock pot or clean bucket. Add the turkey and refrigerate for 4 to 6 hours. If you don’t have enough room in your fridge for the turkey, you can use a small, clean ice chest and add a bag of ice to the brine.
2. Remove turkey from brine, rinse with cool water and pat inside and out dry with paper towel.
3. Place turkey breast side up on a wire baking rack over a rimed backing sheet or roasting pan. Refrigerate uncovered in fridge for at least 30 minutes or up to 24 hours. The longer drying period will air dry the skin and produce a very crisp skin.
4. To make the optional herb paste, process herbs, garlic lemon zest, salt and pepper in food processor until coarse (20 seconds). Add mustard and olive oil and process until it forms a smooth paste.
5. Heat oven to 425 degrees and line large V rack with heavy duty foil and poke lots of holes in the foil. If you don’t have a V rack you can use a wire backing rack and rimed baking sheet, but you might have to drain the baking sheet a couple times as you bake to turkey.
6. Remove turkey from fridge and set breast side up on baking sheet. Using your hands, carefully loosen skin from breasts, thighs, and drumsticks. Then using fingers, rub 2 to 3 Tbs of paste under skin of breast, thighs, and drumsticks.
7. Rub the rest of paste inside the turkey cavity.
8. To roast turkey, place it breast side down in V-rack over roasting pan. Roast 45 minutes.
9. Remove the turkey from the oven and decrease oven temperature to 325 degrees. Using paper towels, rotate turkey so breast is up. Return to the oven and roast 1 to 2 1/2 hours longer until the thickest part of the breast registers 160 degrees and thickest part of the thigh registers 170-175 degrees.
10. Remove turkey from oven and let rest for 30 minutes. Carve and serve.