01 - In a large skillet, melt butter with olive oil over medium heat. Add the finely chopped onions along with a pinch of salt. Cook, stirring frequently, until the onions turn a deep golden brown and are fully caramelized, approximately 25 to 30 minutes. During the final 2 minutes, stir in the minced garlic and cook until fragrant. Remove from heat and let the mixture cool completely to room temperature.
02 - In a mixing bowl, combine the sour cream, mayonnaise, softened cream cheese, Worcestershire sauce, onion powder, garlic powder, salt, and black pepper. Stir until the mixture is completely smooth and all ingredients are evenly incorporated.
03 - Gently fold the cooled caramelized onion mixture into the creamy base. Stir thoroughly to distribute the onions evenly throughout the dip.
04 - Cover the bowl tightly and refrigerate for at least 1 hour to allow the flavors to meld and the dip to firm up to the ideal consistency.
05 - Before serving, give the dip a good stir. Garnish with freshly chopped chives or green onions if desired. Serve chilled alongside potato chips, pretzels, or an assortment of fresh crudités.