Remove and giblets from the cavity, then rinse the bird. Pat the turkey with paper towel to dry the skin. Season the turkey, top and underneath, with salt and pepper.
Preheat the oven to 450 degrees.
In a mixing bowl, combine 1/2c brown sugar, paprika, smoked paprika, yellow mustard, Dijon mustard, chili powder, garlic powder, onion powder, and butter to form a paste.
Rub the paste all over the turkey and gently under the skin.
Place onions and garlic cloves in a shallow roasting pan; place the turkey on top. Roast the turkey for 30 minutes at 450 degrees.
Make a bourbon glaze by whisking together bourbon, honey, apple cider vinegar, and one cup of brown sugar. Baste, brush, or spoon over top of the turkey every 20 minutes.
Cook the turkey until it reaches at least 165 degrees in all locations.
Cover with foil and let rest for at least 30 minutes before carving.