Place the chicken in a large zip-lock bag.   In a bowl, combine the lime juice, pepper sauce, cilantro, onions, peppers, vinegar and cumin. Pour into the bag with the chicken. Seal the bag, place inside a large bowl or baking dish, and refrigerate for at least 4 and up to 8 hours. Turn the bag occasionally to marinate evenly. (Alternately, the chicken and marinade can be placed in a non-reactive baking dish and tightly covered with plastic wrap. Turn the pieces occasionally.)

Preheat a grill to medium-high.

Remove the chicken from the marinade and pat dry. Season both sides with the salt and Essence. Reduce the heat to low or place the chicken on a cooler spot on the grill and grill, with the lid closed, until brown on both sides, cooked through and the juices run clear, about 25 minutes, turning frequently.   Serve immediately.