A traditional crab crack is one of my family's favorite things to make when we all get together. After the crab is boiled, you dump it out on a table covered with newspaper and everyone digs in and gets crackin'. A little drawn butter and some homemade cocktail sauce is all you need to serve with the sweet blue crabs.
For the crabs: Place a large pot of water over medium-high heat outside or indoors. (I like to use a Low Country boil/turkey frying pot.) Add the beer, seafood seasoning and onion and bring to a boil. Boil 10 minutes to season and allow the flavors to develop.
For the cocktail sauce: While the water boils, stir together the ketchup, horseradish, Worcestershire sauce, lemon juice and garlic in a medium bowl. Season with salt if desired.
Add the crabs to the boiling water. Cook until the crabs are reddish-orange and cooked through, 15 to 20 minutes. Drain the crabs and spread on a table covered with newspaper or butcher paper. Sprinkle with additional seafood seasoning. Serve with melted butter and the cocktail sauce.