Cook chopped bacon in a skillet over medium heat until crisp
Remove bacon and drain most of the fat, leaving a few tablespoons in the pan
Add diced onion and cook until soft and golden
Add minced garlic and cook briefly
Stir in brown sugar, apple cider vinegar, brewed coffee, maple syrup, and a little water
Add the cooked bacon back to the pan
Simmer on low heat until thick and jam-like
Stir occasionally and cook until the liquid reduces
Season with black pepper and adjust sweetness or acidity if needed
Let cool slightly
Transfer to a jar or container
Refrigerate before serving