Razor clams are growing in popularity and can be found at good fishmongers. They’re available from September to the end April in the U.K. (months with the letter R in them). They should be alive when purchased, any opened shells should close when lightly tapped, discard any that don’t close or have a broken shell (be careful as their shells are brittle). When preparing rinse under plenty of running tap water to remove any sand. Be careful not to overcook the clams as they can become rubbery.