Charred Onion Dip

Yields
Approximately 6 cups

From chef Kevin Johnson of the Grocery in Charleston, South Carolina

5 pounds onions, very thinly sliced

12 thyme sprigs, picked and minced

6 ounces butter

Olive oil

Salt and pepper

1 cup buttermilk, plus more if needed

2 cups sour cream

1 cup Duke’s mayonnaise

¼-½ cup sherry vinegar

Preheat oven to 400 degrees. Add onions, butter, olive oil, and thyme to a nonstick dutch oven and cover with lid. Bake for 45 minutes, stirring every 15, until onions are deeply caramelized. Remove from oven and cool to room temperature.
In a blender or food processor, purée onions with buttermilk. Add sour cream, mayonnaise, and sherry vinegar and puree until very smooth, adding more buttermilk if necessary.
Adjust acidity with more vinegar, and season with salt and pepper.