01 - In a large skillet, melt the butter with olive oil over medium heat. Add the finely chopped onions along with a pinch of salt. Stir frequently and cook until the onions turn a deep golden brown, approximately 25 to 30 minutes. During the final 2 minutes, stir in the minced garlic. Remove the skillet from heat and let the onion mixture cool completely.
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 seasonings are evenly incorporated.
03 - Gently fold the cooled caramelized onion and garlic mixture into the creamy base, blending thoroughly so the onions are evenly distributed throughout the dip.
04 - Cover the bowl tightly and refrigerate for at least 1 hour to allow the flavors to meld together. The dip tastes best when chilled overnight.
05 - Before serving, give the dip a good stir. Top with freshly chopped chives or green onions if desired. Serve chilled alongside potato chips, pretzels, or an assortment of fresh crudités.