This recipe is from Martha Stewart. It is to die for!!!!! So great on hamburgers, or with cheese and crackers. Or served with biscuits. The uses are endless! You can even place in jars to give as gifts.
In a large skillet, cook bacon over medium-high, stirring occasionally, until fat is rendered and bacon is lightly browned, about 20 minutes. With a slotted spoon, transfer bacon to paper towels to drain.
Pour off all but 1 tablespoon fat from skillet and add onions and garlic. Cook until onions are translucent, about 6 minutes.
Add vinegar, brown sugar, maple syrup, and coffee and bring to a boil, stirring and scraping up browned bits from skillet with a wooden spoon, about 2 minutes. Add bacon and stir to combine.
Transfer mixture to a 6-quart slow cooker and cook on high, uncovered, until liquid is syrupy, 3 1/2 to 4 hours.
Transfer to a food processor; pulse until coarsely chopped.
Let cool, then refrigerate in airtight containers, up to 4 weeks.