Combine all ingredients except the shrimp and lettuce.
Whisk thoroughly until well blended.
Chill before serving over the shrimp on lettuce beds.

This is another one of those classic New Orleans dishes that appears on every menu in town.
However, the variations are endless and exciting.
Traditionally this great dressing is served over cold shrimp, but I find that it goes well with many cold seafoods and seafood salads.