2 large yellow onions
4 tbsp. unsalted butter
1/4 c. vegetable oil
1/4 tsp. ground cayenne pepper
1 tsp. salt
1/2 tsp. ground pepper
4 oz. room temperature cream cheese
1/2 c. sour cream
1/2 c. mayonnaise

Cut the onions in half, then slice them about 1/8-inch thick half rounds (you should have about 3 cups of onions). Heat the butter and oil in a large sauté pan on medium heat. Add onions, cayenne, salt and pepper and sauté for 10 minutes. Reduce heat to medium-low and cook, stirring occasionally, for 20 more minutes, until onions are browned and caramelized. Allow onions to cool. Place cream cheese, sour cream and mayonnaise in a bowl; use an electric mixer and beat until smooth. Add onions and mix well. Serve at room temperature.