Combine the bread chunks and buttermilk. Mix thoroughly and refrigerate.
Light your grill and set it up for two zone cooking. Add a large chunk of oak wood and establish the temperature at 385°F.
In a large mixing bowl, combine all ingredients (except sauce, and two tablespoons of the parsley) with buttermilk-soaked bread and mix with hands, being careful not to overwork the mixture. Place the mixture in the refrigerator for ten minutes while the grill is preheating.
Form the mixture into two equally sized loaves on the parchment paper.
Transfer the parchment paper to a wire cooling rack, then place the rack on the grill over indirect heat. Allow the loaves to smoke for 40 minutes, or until the internal temperature is 155°F.
Glaze each loaf with the sauce and allow them to continue to smoke for an additional 5-10 minutes, or until the internal temperature is 160°F.
Remove the loaves from the grill and garnish with remaining parsley.