In a Dutch oven or large pot, heat oil and sauté two chopped onions and chicken parts until onion and chicken are browned, about 15-20 minutes. (Important: The longer the onion cooks in the chicken, the better the flavor.) Add remaining ingredients except salt and pepper. Bring to boil, then simmer for about 2-3 hours, occasionally skimming off foam. When cooked, strain the stock into a container and discard solids, or cut solids up into pieces and add back to soup. Add salt and pepper to taste. Cool stock and skim the fat. Add Orzo or Acine de Pepe pasta if desired.