1. Place the pork in a heavy 12-inch skillet or Dutch oven. Add the orange juice, water, and 1 teaspoon of the salt and bring to a boil over high heat. Reduce the heat to medium and simmer for 40 to 45 minutes, or until most of the liquid has cooked away and the meat is lightly browned and has rendered most of its fat. Set aside to cool.
2. Meanwhile, place the chiles in a bowl, cover with hot water, and soak for 10 to 15 minutes, until softened.
3. Place the chiles, along with 1 1/2 cups of their soaking liquid, in a blender or food processor, along with the onion, garlic, parsley, oregano, cumin, the remaining 1/4 teaspoon salt, the pepper, and vinegar and puree until completely smooth.
4. When it is cool enough to handle, shred the pork with your hands or two forks and place it and any juices in a large bowl.
5. In the pot in which the meat was cooked, heat the oil over medium heat. Pour in the chile puree, bring to a simmer, and simmer for 8 to 10 minutes, stirring often, until thickened and darkened.
6. Toss in the shredded meat and juices and cook until the meat has absorbed most of the chile sauce, 20 to 25 minutes. Taste for salt. Serve with avocado, salsa verde, corn salad and pickled onions.
