Combine the cilantro, orange juice, olive oil, cayenne pepper, garlic, and salt in a large bowl. Stir well with a whisk.
¼ cup chopped cilantro, ¼ cup freshly squeezed orange juice, ¼ cup olive oil, plus more for drizzling, ½ teaspoon cayenne pepper, 3 teaspoons minced garlic, about 6 cloves, ¾ teaspoon salt
Reserve ¼ cup of marinade in a small bowl and set aside.
Place chicken in the bowl with the marinade, turning to coat. Allow to sit at room temperature for 20 minutes, turning occasionally.
2 boneless skinless chicken breasts, about 1 ½ pounds
While the chicken marinades, preheat the oven to 450°F. Place a large rimmed baking sheet in the oven while it preheats.
Remove the sheet pan from the oven, drizzle with some olive oil and place onions in the middle of the pan in an even layer.
1 red onion, cut in half and then sliced
Remove the chicken from the marinade and place it on top of the onion slices. Sprinkle generously with salt and pepper.
Return the sheet pan to the oven and roast for 32-35 minutes or until chicken reaches 165°F and flip the chicken halfway through.
Remove from the oven and allow to rest for 2 minutes.
Place the chicken and the onions in the bowl of a stand mixer fitted with the paddle attachment, scraping any of the crispy onions from the sheet pan. Shred on low speed, until desired shredding is achieved. (You can also use two forks to shred the chicken.)
Add the reserved marinade, stir well and taste. Adjust salt and pepper, if needed.
Spoon the chicken mixture into flour tortillas and top with avocado slices, queso fresco and cilantro. Serve with lime wedges.
cilantro, avocado, queso fresco, pico de gallo, lime