Saute the onions in a skillet over medium-low heat until translucent and caramelized, about 10 minutes. Add the brown sugar and stir until dissolved. Deglaze the pan with both vinegars and the wine. Simmer on medium-low heat until all the liquid has been evaporated, about 15 minutes.
This recipe was provided by a chef, restaurant or culinary professional. It has not been tested for home use.
Recipe courtesy of Justin Broome, Fuel Charleston, SC