Fresh espresso, from a real-deal machine, is key to this sauce from Franklin Barbecue in Austin, Texas. If you don’t have such a setup, visit a legit coffee shop to have them pull you a shot, and mix up the sauce there, the chef suggests. “I know it sounds weird and may even be slightly embarrassing, but the results are worth it.”
Mix the ketchup, both vinegars, the soy sauce, garlic and onion powders, and sugar together in a saucepan and bring to a simmer over medium heat, stirring occasionally. Remove from the heat, stir in the espresso, and then add the brisket drippings to taste. Let cool, then transfer to a jar, bottle, squeeze bottle, or however you want to store it. Store in the refrigerator for up to 2 weeks.