Choose large or jumbo shrimp, peeled and deveined, with tails on
Bring a large pot of salted water to a boil
Add aromatics if desired, such as lemon slices, bay leaves, or peppercorns
Prepare an ice bath in a large bowl
Add shrimp to the boiling water
Cook until shrimp turn pink and opaque, about 2 to 3 minutes depending on size
Remove shrimp immediately with a slotted spoon
Transfer shrimp to the ice bath to stop cooking
Chill shrimp completely for several minutes
Drain well and pat dry
Serve cold with cocktail sauce and lemon wedges