With their long claws and fanned tails, Crayfish resemble miniature lobsters. Unlike lobster, crayfish are freshwater shellfish that grow to be about 10 cm (4 inches) long. Crayfish aren't native to the UK, but since their introduction from the US they have colonised many waterways and you'll find them on sale at supermarkets and fish markets. Crayfish are commonly boiled in the shell after a cleaning process called purging.
Place the unopened sack of live crayfish in the ice chest and fill it with cold water. Agitate the bag to release the dirt. Drain and repeat.
Open the bag and pour the live crayfish into the ice chest. Fill the chest with cold water. If any of the crayfish float, they're dead -- discard them.
Add 250 ml (1 cup) of salt to the ice chest and allow the crayfish to purge for 15 minutes. Drain the ice chest and refill with water. Allow the crayfish to purge for another 15 minutes, drain and repeat, if necessary, until the water stays clean.
Fill a large cooking pan with water. Add seasoning to taste, or according to the packet instructions if you're using shop-bought seasoning.
Bring the pan to a boil. Add the crayfish. When the water comes back up to boiling, boil the crayfish for five minutes, then turn off the heat.
Let the crayfish sit in the seasoned water for 15 to 30 minutes. The longer they soak, the spicier they'll be.
Drain and serve hot with lemon, chilli sauce or melted butter, or add shelled crayfish to any recipe that calls for prawns, crab or lobster meat.
To shell, hold the tail in one hand and the head in the other. Twist, and pull the head off. The meat is in the tail.
If you prefer, you can steam your crayfish for 10 minutes in a large pan with a steamer basket inserted. Don't season the crayfish until after they've been steamed.
Watch out for the crayfish claws while you wash them.