To prepare the marinade, in a large bowl, combine the olive oil, achiote paste, orange juice and lemon juice and stir well, then add the chicken thighs. Cover and marinate in the refrigerator overnight.

To prepare the vegetables, in a large sauté pan over medium heat, warm the olive oil. Add the garlic and cook, stirring occasionally, until lightly browned. Remove and discard the garlic cloves. 

Add the onion to the pan and cook, stirring occasionally, until translucent. Add the poblano chiles and bell pepper and cook, stirring occasionally, until warmed through. Set aside.

To grill the chicken, prepare a medium-hot fire in a grill.

Remove the chicken from the marinade and shake off the excess. Place the chicken, skin side down, on the grill and cook until the skin begins to brown. Flip the chicken and cook, turning often, until the juices run clear, finishing the chicken with the skin side down, about 20 minutes. 

To serve, transfer the chicken to a cutting board and cut into 1-inch chunks. Add to the vegetables and reheat if needed. Serve with guacamole, warm tortillas and rice and beans.