Chop the bacon into a paste with the garlic, thyme, and sage. Make small incisions between the muscles of the rabbit pieces and pack the seasonings into them. Rub each piece well with vinegar, salt, and pepper, and marinate in the oil, turning occasionally, for 4 to 6 hours.
While the rabbit is marinating, put the fresh or vacuum-packed chestnuts in the preheated
Build a good fire in the grill and let the flames die down to a hot bed of coals. During this time soak the hickory chips in water for at least 30 minutes. Drain the chips and add to the fire. Place the rabbit on the grill and brown well on all sides, about 15 to 20 minutes total cooking time. Watch carefully and do not let the meat overcook.
Combine the chestnut flour, cornmeal, sugar, and salt in a bowl. Pour the boiling water over, stir well and let sit for 10 minutes. Separate the eggs and reserve the whites. Beat the yolks with the buttermilk and stir into the batter. Add the cheese and soda. Beat the egg whites until stiff and fold in. Melt the butter in the skillet or sauté pan over medium heat. Pour the batter into the skillet all at once. Arrange the rabbit pieces over the top of the batter and put into the preheated oven immediately.
Reduce heat to 325°F (163°C).