1 Mix all the lemongrass dressing ingredients together. To kill the live crab if using, turn each one in turn on its back with its eyes facing you. 2 Drive a thick skewer or a long, thin- bladed knife between the eyes into the centre of the crab. Lift up the tail flap and drive the skewer through the underside of the crab - when the crab is dead, it will go limp. 3 For both the uncooked and cooked crabs, break off the tail flap and discard. Break off the claws, cut them in half at the joint and crack the shells off each piece with a hammer. 4 With a large-bladed knife, halve the body section of the crab and gently tug on the legs to pull the body away from the back shell. Use a knife as a lever if you need to, but it should come out quite easily with the legs attached. 5 Turn each piece over and pick off the dead mans fingers. Discard the back shells or save for making stock. Take a large pan and rest some sort of trivet in the bottom on which to rest a plate - a couple of pastry cutters or an upturned plate will do. Pour in water to not quite cover the trivet and boil. 6 Pile the pieces of crab onto a heatproof plate and lower it into the pan. 7 Cover and steam for eight minutes by which time the crab should be cooked. If you are using cooked crabs, give it just 3-4 minutes to heat it through. 8 To serve, arrange the pieces of crab attractive on a large warmed serving plate. Spoon over the lemongrass dressing and serve straight away. Recipe by: Rick Stein