Peel and slice Yellow Onion (4) into rings about 1/8 inch to 1/4 inch thick.
Heat Salted Butter (4 tablespoon) over low to medium-low heat. Cook the onions slowly in the butter for 40 minutes, stirring occasionally.
Remove onions from heat and let cool. Chop into small pieces
In a large bowl, combine the Cream Cheese (4 ounce) and Sour Cream (1 cup) until smooth. Stir in the Mayonnaise (1/2 cup), Worcestershire Sauce (1 teaspoon), and Ground Black Pepper (1/2 teaspoon), Cayenne Pepper (1/4 teaspoon), Salt (1/2 teaspoon), and Hot Sauce (to taste).
Fold in Sharp Cheddar Cheese (4 ounce) and then the cooled caramelized onions until well combined. Serve at room temperature or chilled with your favorite Cape Cod Chips and Snyder's of Hanover Pretzel snacks. Serve and enjoy!