To make the spice rub: Combine paprika, black pepper, sage, thyme, granulated
garlic and salt. Season pork butt with the rub, pressing onto the surface and
coating it evenly. Place meat on a roasting rack in a roasting pan, and roast in
the oven for 15 minutes, to get a nice brown color on the meat's surface. Reduce
oven temperature to 250 F.
Carefully transfer pork butt to a large ovenproof casserole or Dutch oven. In a
separate bowl, mix beer and maple syrup until well combined. Pour over pork, and
add garlic and celery to the casserole. Cover casserole tightly with aluminum
foil, and cook in the oven for about 2 hours until meat is tender (when soft to
touch or when you can gently run a paring knife through it).