Place bacon pieces in a cold cast-iron skillet and turn the heat to medium. Cook until the bacon grease renders, and it's cooked halfway.
Add onion to the rendered bacon grease. Cook until softened, about four to five minutes. In the last 30 seconds, add the garlic, stirring constantly.
Stir together the tomato sauce and tomato paste. Add the coffee, apple cider vinegar, molasses, maple syrup, dark brown sugar, Worcestershire sauce and spices.
Stir the drained beans into the sauce. Lay the bacon pieces directly on top of the beans rather than stir them into the mixture.
Place the beans in the smoker uncovered. Smoke until cooked through. Alternatively, you can bake in an oven.
After smoking or baking, stir in the bourbon. This is optional, but it adds a wonderful flavor. Enjoy every bite!