Fulfilling a double order on the "Sauced" request line from Serious Eater Spencer, I first tackled bacon jam and am making good on the remaining sauce, onion jam.
Much like the bacon jam, onion jam is a sauce that's slowly simmered until it becomes thick and syrupy. I decided to go the "red" route here and started with four red onions sliced thin and cooked until translucent. Then I added red wine in as the main liquid, along with brown sugar, thyme, balsamic vinegar, and salt.
After an hour, the mixture was cooked down to the thick consistency I wanted. At this point it looked like a pile of caramelized onions, but the flavor was so much more than that.
The onions and sugar did create a nice sweetness, but the reduced wine and balsamic overtook that to make a fruity tartness the first and last flavors tasted in this sauce. The onions, while cooked down considerably, still retained just the slightest of crunch, which also gave the onion jam a nice texture.
I used the onion jam as a burger topping, but it could be great as so much more, like spread on crackers for a simple snack, mixed with some cream cheese and/or sour cream for a dip, or topped on grilled meats or veggies.