Combine all ingredients in a small saucepan over medium heat. Bring to a boil, stirring until ingredients are completely incorporated. Reduce heat to low and gently simmer until flavors have melded and sauce has thickened enough to coat the back of a spoon, about 30 to 40 minutes.
Remove from heat and let cool to room temperature. If not using right away, cover and refrigerate for up to 2 weeks.