Preheat the oven to 400°F (200°C).
Prepare the marinade by whisking together the orange juice, zest, olive oil, minced garlic, cilantro, salt, black pepper, and red pepper flakes.
Cut the chicken into bite-sized pieces.
Add the chicken pieces to the marinade, ensuring they are well coated.
Line a baking sheet with parchment paper and spread the marinated chicken pieces in a single layer.
Bake the chicken for 15-20 minutes, or until cooked through and golden brown.
Remove the chicken from the oven and let it rest for a few minutes.
Serve warm, garnished with additional cilantro and orange slices, if desired.