Heat a medium heavy-bottomed pan over high heat. Add the butter, onions and garlic and saute until the onions are translucent and soft.
Turn the heat down to medium, add the salt, black pepper, cayenne pepper and chipotle peppers and cook for 5 minutes.
Add the ketchup, 3/4 cup water, brown sugar, lemon juice, red wine vinegar, liquid smoke, yellow mustard and Worcestershire sauce and cook for 15 minutes.
With a hand mixer, blend the sauce until smooth. There will be some lumpiness from the onions and garlic, and if you like, strain these out through a sieve. Otherwise, simmer the sauce on low for another 15 minutes.
Remove and cool. Store in a plastic container in the fridge for up to 1 month.
This recipe was provided by a chef, restaurant or culinary professional. It has not been tested for home use.