In a skillet, cook bacon until crisp. Remove bacon and drain on paper towels. Discard all but 2 Tbsp. bacon fat. Cook onion in bacon fat until translucent, about 3 minutes, then add garlic and cook 30 seconds longer. Remove mixture from pan and let cool. Crumble bacon when cool enough to handle.
In a large bowl combine beef, bacon, onion mixture, Worcestershire sauce and salt and pepper, and mix well. Form into 24 small patties and chill.
Preheat grill to medium; oil when hot. Cook burgers for about 7 minutes for medium rare, turning once halfway through. Serve burgers on rolls.