Make the marinade. In a blender (or using an immersion blender), combine the chipotle peppers, adobo sauce, garlic, oil, white vinegar, ancho chili powder, salt, cumin, oregano, and black pepper. Blend until completely smooth.

Marinate the chicken. Place the chicken thighs in a large bowl or zip-top bag. Pour the marinade over the chicken and toss thoroughly to coat every piece. Cover and refrigerate for at least 2 hours and up to 12 hours for best texture and flavor. Remove the chicken from the refrigerator about 30 minutes before cooking to take the chill off.

Grill or sear. Preheat an outdoor grill to high heat (475–500°F), or heat a large cast iron skillet over high heat until very hot. Lightly oil the grates or skillet. Place the chicken on the grill or in the pan and cook undisturbed for 4–5 minutes, until deeply charred and caramelized on the bottom. Flip and cook another 4–6 minutes, or until the internal temperature reaches 170–175°F.

Rest and chop. Transfer the chicken to a cutting board and let rest for 8–10 minutes. Slice into strips, then chop into small ½-inch pieces. Sprinkle evenly with the lime juice and toss to coat. Taste and season with additional salt and pepper if needed.

Warm the tortillas and serve. While the chicken rests, warm the tortillas directly over a gas flame, on the grill, or in a hot dry skillet until soft and lightly blistered. Stack two tortillas together for each taco. Fill with chopped chicken and top with diced white onion and fresh cilantro. Serve immediately with extra lime wedges for drizzling.