Cook bacon pieces over medium heat in a skillet until crispy.
Discard all but 2 tablespoons of bacon fat (I put extra bacon fat in a mason jar). Reduce heat to low and add in red onions.
Cook onions low and slow until caramelized, about 45 minutes to an hour.
Add in minced garlic, cooking for an additional 2 minutes.
Add in brown sugar, coffee, bourbon, maple syrup, and balsamic vinegar to the skillet.
Raise to medium low heat and bring to a simmer. Allow to thicken until mixture reaches jam-like consistency, 5-10 minutes.
Chop bacon into about ¼ inch pieces and add into skillet. Stir to combine.
Serve immediately on crackers or as a burger topping, or store in a mason jar/air tight container in the fridge for up to 4 weeks.
