Blend until the sauce is smooth and evenly colored.
Finely chop up
Cook
Place the cooked shrimp in the fridge until it's cold. Instead, it's easier to buy cooked shrimp and merely defrost it.
Serve by placing the sauce in a bowl, placing the bowl in the middle of a platter, and arranging the shrimp around it. Present each guest with a small bowl that has some chopped lettuce in it, and let them pour over sauce and shrimp as they desire: non-seafood lovers can still enjoy the lettuce/sauce mix with some bread. If you have excess sauce, you should keep it covered in the fridge or the top will form a crust.