In a large skillet over medium high heat, melt butter and add in sliced onions and salt. Cook and stir for 5 minutes, until onions are just beginning to softened.
Add in the sugar and water and stir to combine, turn down the heat to medium and continue to cook and stir occasionally until the onions are very tender and a caramel color, about 20-25 minutes
Remove the onions from the heat and allow to cool
In a large mixing bowl combine the cream cheese, sour cream, mayonnaise and garlic powder. Mix together with an electric mixer until smooth and creamy, about one minute
Fold the caramelized onions into the cream cheese mixture and serve immediately or store in the refrigerator in an air tight container until ready to serve.
Garnish with sliced green onion if desired
Video
Notes
this recipe can be made a day ahead, the flavors will be even more intense
serve with your favorite sliced vegetables, bread or potato chips