A piastra is a heavy cast-iron pan or griddle that can be heated to about 400 degrees. It is a perfect medium for cooking seafood — especially shrimp, calamari and lobster. It makes cooking lobster, in particular, easy and fun and the results are outstanding. The trick is first to poach the lobster for five minutes. Then it can sit in the fridge for up to twenty-four hours. The hardest part is splitting the lobster — it takes a sure hand. The instructions are precise and simple, but bold. The piastra sears the lobster flesh so that it becomes crispy and sweet at the same time.
Prepare the piastra by placing the empty pan over low heat for 30 minutes.
Have a large pot of boiling water ready to cook the lobsters. When the water comes to a boil, add 1 tablespoon sea salt, drop in the lobsters and cook them for 5 minutes, then plunge them into a sink filled with cold water. Remove and keep cold.
Place a lobster on a wooden board, head up. Using a 10-inch chef’s knife, plunge the knife point directly into the lobster at the cross on its head. Split the lobster in half and crack the claws. Repeat with the second lobster. Place all the lobster pieces in a bowl and mix with the lemon juice, paprika, and 1 tablespoon of the olive oil.
Cook the lobster halves on the piastra, flesh side down. Cover with a lid or a heatproof bowl. Cook for 5-8 minutes, or until the flesh is white, firm, and springy to the touch.
Dress the arugula with the remaining teaspoon of olive oil and a pinch of sea salt and serve with the lobsters.