Shrimp Cocktail

1.Fill a large bowl with ice and add water to cover; set aside. Cut one lemon into wedges and set aside.
2.In large pot combine 6 cups water, salt, sugar, onion, bay leaves, and parsley. Halve and juice remaining lemon and add to pot. Bring to a rolling boil, then turn off heat and add shrimp to pot.
3.Let sit until shrimp are pink and cooked through, about 3 minutes. Stir to make sure all shrimp are covered with the liquid. If using extra large shrimp, poach for an additional 2 minutes.
4.Remove shrimp from the pot with a slotted spoon into the bowl of ice. Let the shrimp cool off for 10 minutes. Place shrimp on ice or dry and place in a bowl and into the refrigerator for up to a day before serving. Serve with lemon wedges and cocktail sauce.