This is adapted from a dynamite recipe on the blog KevinandAmanda.com
Make the dry rub and the brine solution.
In a medium container with a lid, combine all ingredients for the rub. Mix well, cover and set aside.
In a large bowl, add the salt, water and cider vinegar, stirring thoroughly until most all of the salt is dissolved. When the salt is completely, or mostly dissolved, add the brown sugar, bay leaves (don't crush the bay leaves), garlic and 2 tablespoons of the dry rub (we'll use the rest later). Stir well to combine.
Place the pork roast in a 1 gallon freezer bag or in a large container. Pour the brine solution into the bag until the shoulder is completely covered. Close the bag or cover the container and place in the refrigerator for at least 8 hours and up to 24 (preferred).
Pre-heat the oven to 225 F degrees.
Remove the pork roast from brine solution, pat dry with paper towels, place in a large roasting pan, leaving 1 inch clearance on all sides of the roast to accommodate the cooking juices which will accumulate. Press the dry rub onto the surface of the roast, pressing it so it will adhere to the surface. Generously coat all sides and under any flaps with the rub.
When done make sure the fat layer on the pork roast is on the TOP. Insert a digital probe thermometer into the thickest part of the shoulder, but not touching the bone. Place the roasting pan, uncovered, in the 225 F degree oven on the middle rack.
Monitor the temperature throughout cooking. Do not remove roast from the oven until the center of the pork roast reaches 200 F degrees. The internal temperature should reach at least 200 F degrees to get that tender, falling apart shredded meat. Don’t worry about the long cooking time. It will still be juicy and flavorful because of the brining. Cooking at 225 F degrees, your shoulder will take between 1.5 to 2 hours per pound to cook. My 8 lb. pork roast took 13 hours.
When the pork roast's internal temperature reaches 200 F degrees, turn off the oven, leaving the roast in the oven and the thermometer in the roast. Your pan should have plenty of wonderful cooking juices in the bottom. If not, add 1 cup of water and cover the pan to retain the moisture while your roast is resting.
Let the roast cool (for approximately 2 hours) to an internal temperature of 170 F degrees before removing from the oven.
When the temperature drops to 170 degrees, remove the roast from the oven. Place the roast on a large, clean work surface and remove any remaining fat from the top. Pour the juices from the roasting pan into a fat separator cup to strain and reserve the juices.
Shred the roast with two forks, it will pull apart very easily. Discard the bone. Add back in some of the defatted pan juices. IT’S VERY IMPORTANT to taste and sprinkle with kosher salt as you go.
Transfer shredded pork to 2-gallon freezer bags and refrigerate or freeze. Freeze remaining pan juice separately. You'll use it later when you re-warm the pork.
If frozen, thaw pork and juice over night in refrigerator. Then re-warm in a 350 degree oven for about 10 - 20 minutes. Add in reserved pan juices as necessary to achieve desired level of moisture.
Melt 1 tablespoon butter for every 2 buns and baste the cut side of buns with the butter. Sauté the buns on a griddle over medium temperature until golden brown. Set aside, covered.
Mix pulled pork with your favorite barbecue sauce. Serve on toasted buns with cole slaw.