In a large saut pan, heat EVOO and begin browning the chicken pieces in small batches making sure not to over crowd the pan. Add the onions, garlic, salt and pepper, and stir to combine. Cook until onions and garlic are soft, about 2-3 minutes. (If your pan is too small to cook all the chicken at once without overcrowding, work in batches, reserving cooked chicken on a plate. Add additional EVOO, if needed, to saut onions and garlic.)
In a bowl, whisk together the brown sugar, cider vinegar, Worcestershire sauce, hot sauce, tomatoes and chicken stock. Pour into the pot with the chicken. Let this mixture cook for about 15-20 minutes or until reduced.
To serve, split the muffins horizontally. Cover a cookie sheet with some foil and arrange the split muffins on the tray cut-site up and brush with melted butter. Toast under the broiler for 1 minute. Place the toasted corn muffin halves on top of the skillet stew and sprinkle the chives.