Add 1/2 cup orange juice, 3 chipotle peppers, 4 cloves garlic, 2 tablespoons cilantro, 2 tablespoons light brown sugar, 1 tablespoon olive oil, 1 tablespoon achiote paste, 1 tablespoon apple cider vinegar, 1/2 tablespoon ancho chili powder, 1 teaspoon salt, 1/2 teaspoon ground cumin, and 1/2 teaspoon dried oregano to a food processor bowl. Cover and pulse until well blended.
Add 1 pound boneless skinless chicken thighs to a large mixing bowl or baking dish. Pour the marinade over the chicken. Spread 1 small yellow onion cut into slices, over the chicken and mix to combine.
Cover the bowl/dish with plastic wrap and marinate in the fridge for 4 hours to overnight.
When you're ready to cook, preheat the oven to 425 degrees F. Drizzle 2 tablespoons olive oil over a baking sheet.
Place the chicken and onions onto the prepared pan. Add 1 cup pineapple to the marinade still in the bowl. Toss the pineapple to coat and then arrange it over the chicken.
Bake for 15-18 minutes or until the chicken is cooked through to an internal temperature of 165 degrees F. Then broil for 1-2 minutes.
Remove from the oven. Transfer the chicken to a cutting board and chop. Serve warm in corn tortillas with pineapple, chopped onion, and cilantro if desired.
Notes
Nutritional information includes taco ingredients.