Ingredients
Method
- Melt butter in large skillet over medium; add onions, salt, and pepper.
- Cook slowly 30-35 minutes, stirring occasionally, until deeply caramelized and golden brown.
- Add thyme and garlic during final 2 minutes; remove from heat and cool completely.
- Combine sour cream, mayonnaise, and Worcestershire in medium bowl.
- Fold in cooled onions until combined.
- Cover; refrigerate at least 2 hours or overnight to meld flavors before serving.
