For marinade:
6 dried guajillo chiles
4 garlic cloves
1/4 cup extra-virgin olive oil
1/4 cup lemon juice (about 2 lemons)
1/4 cup apple cider vinegar
3/4 cup pineapple juice
1 tbsp Aleppo pepper
1 tbsp ground coriander
1-1/2 tsp ground cumin
2 tsp oregano
1 tsp ground chipotle chile (optional)
1/2 tsp ground cardamom
1/2 tsp paprika
4 tsp kosher salt
For chicken:
4 lbs boneless, skinless chicken thighs,
trimmed of fat
1 onion, sliced into 3/4-inch wedges (with
core attached, to hold wedge together) Kosher salt
1/2 bunch parsley, coarsely chopped
1/2 bunch cilantro, coarsely chopped
Cover guajillo chiles in hot water and let sit until soft, about 15 minutes. Remove stems and seeds; chop into 1-inch pieces. Combine all remaining marinade ingredi- ents in a blender and mix to incorporate. Add chiles and blend until smooth.
Bisect each chicken thigh widthwise to make two thin slabs. (Press your palm onto thigh and cut using small sawing motions.) Place slabs in a medium bowl or resealable bag, add marinade, and marinate in refrig- erator at least 4 hours or overnight.
Warm a cast-iron griddle over high heat. Sear marinated chicken in batches (taking care not to crowd the pan), until charred and cooked through, 3 to 4 minutes per side. Set pieces aside as they come off pan and cover to allow meat to rest and reab- sorb its juices. When all chicken is cooked, deglaze pan juices with a little water, then drizzle juices over chicken. Wipe out griddle, raise heat to medium-high, and grill onion wedges. Season lightly with kosher salt, lower heat to medium, and cook until tender, about 10 minutes.
Slice chicken lengthwise into 12-inch strips and place in a serving bowl or on a platter. Fold in onion wedges. Adjust salt and heat to taste. Sprinkle with parsley and cilan- tro and serve with flatbreads or tortillas. Makes 4 to 6 servings.