Lettuce Sauce

Combine the lettuce, egg yolk, capers, lemon juice, parsley, red onion, garlic, mustard, and basil in the bowl of a food processor fitted with the blade and process until smooth. Then, with the machine running, pour in the olive oil slowly through the feed tube. Season aggressively with salt and pepper. Chill until ready to use. Serve over cold poached fish or chicken or, as Emeril does, smoked salmon, hard boiled eggs and tomato slices.