I saw this dish mentioned in comments over at Balloon Juice the other day. As is my wont, I selected the term and did a Google search. This was a top result. The Serious Eats joint is chock full of good recipes and cooking techniques so anytime I see them covering a recipe I’m interested in I go look.The recipe gets its start by toasting dried peppers. Here I have anchos, New Mexico chilis, and pasillas.I cut a Boston butt into cubes and browned them in a little oil. I cut up a 7lb butt so I had to do this in two batches.I like onions so there are plenty here sweating down in the pan the pork was browned in.Meanwhile, the other ingredients were added – orange juice concentrate, chicken broth, chipotles, vinegar and fish sauce. It simmered for a while and then was pureed in a blender and returned to the pot.Add back the browned pork and the onions and the rest of the spices and bring to a boil, then simmer, partially covered, for several hours until the sauce has reduced enough to suit.