This method can be used on most crabs. Mud crab, shown here, needs extra care as the shell is very hard.
Twist the claws to remove them. Use your thumb as a lever to prise off the hard top shell. Scoop out any creamy brown meat and reserve. Wash and dry the shell well.
Discard the soft stomach sac from the main body of the crab and remove the grey spongy fingers (gills). Scrape out and reserve any more creamy brown meat.
Cut the main body of the crab in half lengthways, then remove the white meat from the body using the end of a teaspoon or fork.