Mix together pulled pork from pork roast with about 1 cup of bbq sauce until well-coated. Add onion and garlic and mix well. Using tongs, stuff pulled pork mixture into each half of poblano pepper and place into a skillet. Cover with aluminum foil.
Place in preheated oven and bake for 10 minutes or until heated through and the pepper begins to soften slightly. Remove foil and top with grated cheese. Return foil cover and bake an addition 5 minutes, or until cheese has completely melted.
Serve with additional BBQ sauce on the side.
Cooking and Prep Time does not include time to prepare the pork roast or the bbq sauce.