Mix together the crab, mashed potatoes, ginger, lime rind, chilli and mayonnaise. Season the mixture well with salt and pepper. Divide the mixture into 12 portions and shape into cakes with your hands.
Heat the vegetable oil in a frying pan and fry the crab cakes for 3–4 minutes on each side until they are golden brown.
Make the salsa by mixing together the black-eyed beans, red pepper and sweetcorn. Squeeze over the lime juice and stir in the olive oil. Season with salt and pepper. Finally, mix in the chopped coriander.