
Caramelized onion dip is packed with slow-cooked onions, cream cheese, sour cream, and mayonnaise.
In a large skillet over medium heat, melt butter. Swirl in oil. Add onions and 1/2 teaspoon salt. Cook, stirring occasionally, until beginning to break down and soften, 10 to 12 minutes. Reduce heat to medium-low and cook, stirring occasionally, until golden and deeply caramelized, 40 to 55 minutes more. Transfer to a medium bowl and let cool completely.
Stir in cream cheese, sour cream, and mayonnaise; season with salt and pepper. Top with chives. Serve with chips alongside.