Red Onion Jam
A sweet and sour topping of carmelized red onions that is perfect to dress up a burger.
Place a small saucepan over medium-low heat and add the butter. Once melted add the sugar and red onion. Stir to combine and cover, cook for about 20 minutes. Give it a stir once in a while to ensure it's not sticking or burning.
Remove the cover and add the white wine and vinegar. Increase heat to medium and cook, stirring frequently until all the liquid has been absorbed and the onions are very soft and caramelized, about 30 minutes.
Cool. Will keep in the refrigerator for up to 2 weeks in a sealed container.