Stir together 1 cup ketchup, minced garlic, 2 Tablespoons brown sugar, 2 Tablespoons pure maple syrup, 2 Tablespoons Worcestershire sauce, 1 1/2 Tablespoons apple cider vinegar, 1 teaspoon smoked paprika, 1 teaspoon chipotle in adobo sauce, and 1/2 teaspoon freshly ground pepper in a medium saucepan. Bring to a boil over medium heat, then reduce heat to low and simmer for 15-20 minutes until thickened. (Partially cover with a lid to prevent splatters). Remove from heat and allow to cool. Can be stored in the refrigerator for a week.
For the hamburger patties
Mix 2 pounds extra lean ground beef, 2 Tablespoons pureed chipotle in adobo sauce, and 2 Tablespoons Worcestershire sauce together with your hands. Form into 8 patties. Refrigerate until ready to cook.
Heat grill at medium high heat for 10 minutes. Oil grill with an oiled paper towel. Place hamburger patties on the grill. Cook for about 7-10 minutes on each side.
For the burgers
Assemble hamburger patties, cheese, bacon and onions on the buns. Top with a generous portion of the BBQ sauce.