1) Heat the olive oil or garlic oil and butter in a frying pan set over medium heat, and add the diced onion and minced garlic.
2) Sauté slowly, stirring occasionally, till the onion is soft and golden brown, about 25 minutes. Add the water/wine to the onions, and continue to sauté gently till the liquid is mostly absorbed, stirring frequently, about 3 to 5 minutes.
3) Remove the pan from the stove, and transfer the onion and garlic to a plate to cool.
4) Mix the sour cream, cream cheese, and mayonnaise till smooth. Add the onions.
5) Add salt and Worcestershire sauce to taste, and onion powder, if desired.
6) Refrigerate till ready to serve.
Yield: 2 1/2 cups dip.