Thinly slice the yellow onions. In a large skillet over medium heat, melt the butter until bubbly. Add the sliced onions and cook for 20-25 minutes until golden brown and fragrant.

In a mixing bowl, combine softened cream cheese, sour cream, and mayonnaise until smooth.

Once caramelized, let the onions cool slightly before mixing them into the creamy mixture along with garlic powder, salt, and pepper. Stir well.

Cover and chill in the refrigerator for at least one hour to enhance flavors.

Serve with chips or fresh vegetables.