Toss shrimp with Old Bay and Cajun seasonings. Refrigerate for 1 hour.
Bring the beer to a boil in a saucepan. Add the shrimp and boil until
firm and pink, about 3 minutes. Drain. Arrange hot shrimp on a lettuce
leaf on a salad plate. Garnish with lemon wedges. Serve with cocktail
sauce.