¾ cup ancho chile powder
1/3 cup Spanish paprika
3 tablespoons ground dried oregano
3 tablespoons ground coriander
3 tablespoons dry mustard
2 tablespoons ground cumin
2 tablespoons kosher salt
1 tablespoon ground black pepper
2 teaspoons chile de arbol
6 lb pork butt
Place pork, fat side up, on work surface. Place on large baking sheet. Season on both sides with salt and pepper then rub the dry rub all over pork; press into pork. Cover with plastic; refrigerate at least 1 hour.
Following manufacturer's instructions and using lump charcoal and 1/2 cup drained wood chips for smoker or 1 cup for barbecue, start fire and bring temperature of smoker or barbecue to 225°F. to 250°F. Place pork on rack in smoker or barbecue. Cover; cook until meat thermometer inserted into center of pork registers 180°F., turning pork and brushing with cold mop every 45 minutes, about 6 hours total. Add more charcoal as needed to maintain 225°F. to 250°F. temperature and more drained wood chips (1/2 cup for smoker or 1 cup for barbecue with each addition) to maintain smoke level.
Transfer pork to clean rimmed baking sheet. Let stand until cool enough to handle. Shred into bite-size pieces. Mound on platter. Pour any juices from sheet over pork. (Can be made 1 day ahead. Transfer pork and any juices to baking dish. Cover with foil; chill. Before continuing, rewarm pork, covered, in 350°°F. oven about 30 minutes.)
Black Pepper Vinegar Sauce
¼ cup rice wine vinegar
2 heaping tablespoons Dijon mustard
2 tablespoons honey
1 teaspoon coarsely ground black pepper
½ cup plus 2 tablespoons canola/olive oil blend
Blend in a blender until emulsified.
Green Onion Slaw
1 cup green onions, coarsely chopped
¼ cup red wine vinegar
2 serrano chiles
2 tablespoons mayonnaise
Salt and pepper
¼ cup pure olive oil
1 head purple cabbage, FINELY SHREDDED
1 small red onion, halved and thinly sliced
¼ cup chopped cilantro leaves
Blend green onions, vinegar, ¼ cup cold water, chiles, mayonnaise, salt, pepper and oil in a blender until emulsified. Place cabbage and red onions in a bowl, add the dressing and stir until combined. Fold in the cilantro and season with salt and pepper to taste.