In a large mixing bowl, mix together the ground beef, black pepper, barbecue sauce and garlic.
Portion into 12 burger patties.
Lay patties out on a cookie sheet and cover with plastic wrap; place patties in the refrigerator.
Melt the butter in a large skillet over medium high heat. Stir in the onions and cook for 5 minutes, or until translucent and just beginning to brown. Stir the cooked crumbled bacon to the onions and set aside.
Prepare a grill or large skillet for medium
As the grill heats, pull beef patties out of the refrigerator; top 6 of the patties evenly with the bacon and onion mixture, top each patty with 1/4 cup shredded cheese.
Place remaining burger patties on top of each burger with filling mixture and press the edges together to seal the filling inside.
Grill or pan fry the stuffed and sealed patties until cooked through to your preference.
*Nutrition information does not include burger bun.Chris suggests that next time I make these I mix the bacon into the burger instead of stuffing it.