Special equipment: 2 cups wood chips (hickory or apple), soaked in water 30 minutes
Heat the oil in a small saucepan over medium heat. Add the thyme, garlic, onions, ancho chile powder, brown sugar, cumin, coriander, orange juice, lime juice, 1/2 water and chipotle, and cook until the sugar is dissolved. Remove from the heat and let cool. Put the pork in a large pan and pour over the marinade. Cover and refrigerate overnight.
Remove the pork from the refrigerator 30 minutes before cooking.
Preheat a charcoal grill for indirect heat and place the soaked wood chips on top of the coals.
Place the pork on the grill, cover and let smoke until the temperature inside the grill is 220 degrees F. Add chips as necessary to continue smoking until the internal temperature of the pork reaches140 degrees F. Then just let the pork finish cooking until the internal temperature reaches about 190 degrees F. This can take about 5 hours. Let the pork rest 30 minutes.
Shred the pork and serve in the warm tortillas topped with some Napa Cabbage Slaw, hot sauce, fresh cilantro leaves and queso fresco.
Whisk the mayonnaise, vinegar, oil and celery seeds until smooth. Season with salt and pepper. Whisk in the green onions and serrano chiles. Place the cabbage and carrots in a large bowl. Add the dressing and the queso fresco, and toss to combine.