Warm the olive oil in a large skillet over medium heat. Add the onions and salt.

Cook for 25–30 minutes, stirring often, until the onions turn soft and golden. Lower the heat if they brown too quickly.

Let the onions cool for 10 minutes, then chop them into smaller pieces.

Stir the sour cream, mayonnaise, lemon juice, garlic powder, and pepper in a bowl.

Fold in the onions and chives. Cover and chill for at least 30 minutes before serving.