For the marinade:

 

6 guajillo chiles, soaked in 4 cups of warm water for 1 hour, or 1/2 cup pure chili

powder

1/4 cup distilled white vinegar

3 tomatillos, husks removed, washed, and rough-chopped

2 cloves garlic, rough-chopped

2 bay leaves, crumbled

1 tablespoon coarse salt (kosher or sea)

2 teaspoons fresh ground black pepper

2 teaspoons dried oregano

1 teaspoon ground cumin

1 teaspoon aniseed

1 teaspoon dried thyme

 

4 to 5 pounds boneless pork shoulder, quartered, then thinly sliced against the grain

2 sweet onions, peeled and cut crosswise into 1/4-inch slices

1/2 fresh ripe pineapple, peeled, cored, and cut crosswise into 1/2-inch slices

 

For serving:

 

20 corn tortillas (preferably freshly made—available at Mexican markets)

Sliced purple cabbage

Sliced or diced avocado

Pico de gallo or other salsa (optional)

1 bunch fresh cilantro, washed, dried, and stemmed

1. Make the marinade:  Drain the soaked chiles, reserving 1 cup soaking liquid.    Tear open each chile and scrape out and discard the seeds.    Rough chop the chiles and place in a blender with the vinegar and 1 cup chile soaking liquid.    Puree until smooth.    Add the tomatillos, garlic, bay leaves, salt, pepper, oregano, cumin, aniseed, and thyme and process to a smooth, pourable puree.     Alternatively, puree the ingredients in a food processor, but in this case, puree the solid ingredients (the chiles, tomatillos, garlic, etc.) first, then add the liquids.

 

2. Layer the sliced pork, onions, and marinade in a nonreactive baking dish large enough to hold them. (Alternatively, divide the ingredients between 2 large resealable plastic bags and massage the bags to distribute the marinade.) Cover and refrigerate for at least 4 hours.

 

3. Set up your Fire Magic grill for direct grilling and preheat to medium-high.   Brush and oil the grill grate.
4. 4. Grill the pineapple slices until golden brown, 3 to 5 minutes per side.     Keep warm on the side of the grill or on a platter.     Grill the pork and onion slices until golden brown, 2 to 4 minutes per side.  (The pork should feel firm to the touch.)

    

   5. Transfer the grilled ingredients to a cutting board, stacking several slices of pork with a slice of onion and pineapple.    Thinly slice through the stack with a sharp chef’s knife to create slivers.

    

   6. Warm the tortillas on the grill for 20 seconds or so per side.    Place some sliced pork, onion, and pineapple on the tortilla.     Have each eater top the filling with sliced cabbage, avocado, pico de gallo, and cilantro.    Serve the tacos al pastor open-face sandwich-style.    To eat, roll it into a tube.