The best way to make a Boston butt is to slow-roast it. Preheat an oven at 325 degrees Fahrenheit. Pat the pork dry and liberally sprinkle the surface of the meat with salt and ground black pepper. Place the meat with the fat cap up on a roasting pan. Use a knife to slightly score the fat cap, creating diamond shapes. Cover the pork with aluminum foil and roast for about five hours or until an instant-read thermometer reads 180 degrees Fahrenheit. Allow the meat to cool at least 20 minutes, and either cut into slices or shred into pulled pork.