Langostino, lobsterette langaustine: a tail by any other name is still as sweet, even if it isn't really lobster. More closely related to hermit crabs than the noble lobster, langoustino is actually called the "squat lobster" when it is alive and shouldn't be confused with "langoustine" which is also known as the Norway lobster, or the Dublin Bay prawn. When you buy the tails frozen, more than likely you are getting langostinos that are already cooked. All you have to do is thaw them and include them in your favourite seafood recipe.
Leave the langostino tails in the bag they came in, and put the bag into a plastic or glass bowl and place the bowl in the refrigerator. Thaw the tails for 24 hours per pound, not longer than two days or you run the risk of contamination. Leaving the tails in the bag will prevent them drying out and getting gummy.
Speed thaw the langostinos by filling the bowl 2/3 full with cold water and adding the frozen tails. Leave them on the worktop for up to two hours. Change the water every 15 minutes or so to halt the growth of bacteria.
Remove the langostino tails from the bag and gently blot them dry with a paper towel or a lint-free kitchen towel. Put them in the bowl and cover it with cling film. Leave it in the refrigerator until you are ready to use the langostino tails.
Choose your recipe. Use langostinos in any recipe that calls for shellfish.
Put the thawed tails between two paper towels and wring lightly with your hands to remove any excess liquid that could affect the outcome of your dish.
Prepare the dish. Langostinos can be tossed in a salad, included in a bisque or soup or tucked into a po' boy sandwich. One of the classic ways to prepare them is to sauté them in butter with garlic and white wine, and pair them with the pasta of your choice.
If you are looking for a simple way to enjoy your langostinos, put the thawed tails into boiling water for no more than five minutes, or they will become rubbery and tough. Dip them in melted butter and enjoy.
If you speed thaw your langostino tails, never use hot water; you run the risk of food poisoning.