Caramelized Onion Dip

2 large yellow onions
4 tablespoons unsalted butter
1/4 cup vegetable oil
1/4 teaspoon ground cayenne pepper
1 teaspoon kosher salt
1/2 teaspoon freshly ground black pepper
1 teaspoon balsamic vinegar
4 ounces cream cheese, room temperature
1/2 cup sour cream
1/2 cup mayonnaise

Cut the onions in half and then slice them into 1/8-inch-thick half-rounds. (Yielding about 3 cups of onions)

Heat the oil and the butter in a large sauté pan over medium high heat. Add the onions, cayenne, salt and pepper and sauté for 10 minutes. Reduce the heat to medium low and continue to cook for 40 more minutes, stirring occasionally (but not too often-the onions should start to stick to the pan) until the onions are browned and caramelized.

Add the balsamic vinegar and continue to cook for about 10 more minutes. Allow the onions to cool.

In a large bowl combine the cream cheese, sour cream and the mayonnaise. Whisk until smooth. Add all of the onions, reserving about a tablespoon for garnish, into the cream cheese mixture. Stir to combine and mix well. Transfer to a serving dish and top with reserved onions. Refrigerate overnight to allow flavors to combine. Serve at room temperature with potato chips.

Makes 2 cups.