Heat olive oil in a large skillet over medium heat.
Add the sliced onions and stir to coat with oil.
Cook the onions, stirring occasionally, for about 30 minutes until they are caramelized.
Remove the skillet from heat and let the onions cool.
In a mixing bowl, combine sour cream and mayonnaise.
Add garlic powder, onion powder, salt, and pepper to the bowl.
Incorporate the cooled caramelized onions into the mixture.
Stir until all ingredients are well combined.
Transfer the dip to a serving bowl and garnish with chopped chives.
Chill in the refrigerator for at least 30 minutes before serving.