2/3 cup prepared yellow mustard (hot-dog style)
1/2 cup packed light brown sugar
1/4 cup sugar
1 cup cider vinegar
2 tablespoons ancho or pure chili powder
1 teaspoon ground white pepper
1/2 teaspoon cayenne pepper
1 teaspoon regular or low-sodium soy sauce
A few squirts of Sriracha (Asian-style chili sauce)
Combine the mustard, sugars, vinegar, ancho or chili powder, white pepper, cayenne pepper and soy sauce in a medium saucepan; stir to combine. Cut the lime in half; squeeze the juice of the halves into the saucepan, then toss the spent halves into the mixture. Cook over low heat for 15 to 20 minutes, stirring occasionally.
Cool to room temperature; discard the lime halves. Add the Sriracha (to taste); stir well.
Use right away, or cover and refrigerate for up to several weeks.
Source: Washington Post