Heat the oil in a heavy bottomed pan over low heat. Add the onions and cook over low heat, stirring, until they golden brown in color. This process will take about 20 minutes. Remove from heat, cool.
In a large mixing bowl, fold together the onions, sour cream, and chives. Add the Worcestershire sauce and garlic salt; adjust to taste. Cover the dip and allow the flavors to mature for at least 2 hours. Serve with chips.