For the salad:
- 1/2 red onion, halved, thinly sliced
- 2 hearts romaine, chopped
For the dressing:
- 1/2 cup mayonnaise
- 1/2 cup sour cream
- 1/4 English cucumber, including peel, sliced
- 1 anchovy fillet, rinsed, patted dry, and roughly chopped
- 1 garlic clove
- 1/4 cup fresh cilantro leaves
- 1 tablespoon red wine vinegar
- Salt and freshly ground black pepper
In a large bowl combine onion slices and romaine. Set aside.
In a food processor, combine all the dressing ingredients and puree until smooth. Adjust seasoning, to taste. Pour half of the dressing over salad and toss. Refrigerate remaining dressing.