Heat a large, high-rimmed sauté pan over medium-high heat. Add bacon and cook until browned and just crisp. (The crisper the bacon, the more texture your jam will have.)
Once bacon is browned, remove from pan and place on a paper towel-lined plate to drain excess fat. Set aside.
Pour out the excess bacon grease into a disposable container, leaving about 1 tablespoon fat in the pan. This will look like a film of fat in the pan. Turn heat to medium-low and add onions. Sauté the onions until translucent.
Add paprika and garlic to the onions and turn heat down to low. Stir a few times to evenly distribute garlic, then add the maple syrup. If using milk stout, add 2 tablespoons brown sugar; if using malt beverage, add 1 tablespoon brown sugar. Cook until the brown sugar has dissolved. When you pull a spoon along the bottom of the pan, the liquid should slowly move back into place.
Add the vinegar and beer (milk stout or malt beverage). Turn to medium-high heat and bring the mixture to a boil. Reduce the heat and add bacon. Allow to simmer gently for 15 minutes, or until the liquid has started reducing. When you pull your spoon along the bottom of the pan, the line you drew should fill back in very slowly.
Turn off heat and let sit for 10 to 20 minutes while you set up your blender (or food processor) with the blade attachment.
Pour the bacon jam into your blender and pulse for 1 to 2 minutes, until the desired consistency is reached. (I prefer the consistency of chutney over that of jelly.)
Refrigerate for 1 hour before eating to allow it to solidify, but sneak in a couple of spoonfuls if you like it warm.
Store in your refrigerator in an airtight container for up to 1 month.