Ingredients:
- 2 lb (900 g) yellow onions (about 4–5 medium), thinly sliced
- 1 tbsp (15 ml) neutral oil (vegetable or canola) or olive oil
- 2 tbsp (28 g) unsalted butter
- 1 tsp (4 g) fine sea salt, divided
- 1 tsp (4 g) granulated sugar (optional)
- 2 tbsp (30 ml) dry white wine, sherry, or water (for deglazing; optional)
- 1 tsp (5 ml) balsamic vinegar or red wine vinegar (optional)
- 1 cup (240 g) full-fat sour cream (or plain Greek yogurt)
- 1/2 cup (115 g) mayonnaise (or plain Greek yogurt + 1–2 tbsp oil)
- 4 oz (115 g) cream cheese, softened
- 1 tsp (5 ml) Dijon mustard
- 1 tsp (5 ml) Worcestershire sauce (optional)
- Freshly ground black pepper, to taste (about 1/4–1/2 tsp)
- Additional salt to taste (start with 1/4 tsp)
- 1–2 tbsp (4–8 g) chopped fresh chives or parsley
- Pinch smoked paprika or a drizzle of olive oil (optional)
- Crispy bacon bits (optional)
Instructions:
- Peel and thinly slice the onions evenly, aiming for about 1/8–1/4 inch (3–6 mm) thickness.
- Heat a large wide heavy skillet over medium heat; add the oil and butter until the butter foams. Add the sliced onions and 1/2 tsp salt, stirring to coat and spreading them into an even layer.
- Reduce heat to medium-low and cook the onions low and slow, stirring every 3–5 minutes to prevent sticking. After about 20–30 minutes, add 1 tsp sugar if using to encourage color. Continue cooking another 15–30 minutes until onions are deeply golden to mahogany and jammy, lowering heat if edges begin to burn.
- If fond forms on the pan, deglaze with 2 tbsp wine, sherry, or water and scrape up the browned bits. Stir in 1 tsp balsamic or red wine vinegar and the remaining salt, taste and adjust seasoning. Remove from heat and let cool slightly.
- Transfer the caramelized onions to a plate or shallow bowl and cool to near room temperature so they won't melt the cream base.
- In a mixing bowl, beat the softened cream cheese until smooth. Fold in the sour cream, mayonnaise, Dijon mustard, Worcestershire sauce (if using), freshly ground black pepper, and about 1/4 tsp additional salt. Taste and adjust seasoning.
- Fold about three-quarters of the cooled caramelized onions into the dip base, reserving some onions for garnish.
- Cover and refrigerate the dip for 30–60 minutes to let the flavors meld (optional but recommended).
- Transfer to a serving bowl and top with the reserved onions, chopped chives or parsley, and a pinch of smoked paprika or crispy bacon if desired. Serve with chips, crudités, or toasted bread.