Combine crab, cayenne, lemon juice and zest, and
season well. Pack into 8 small or 1 large ramekin.
Melt the butter, then pour over until the crab is
covered with a thin film. Top with a parsley leaf if
you like, then cool in the fridge. (It will keep for up to
2 days in the fridge.) To prevent the butter melting,
transport to your picnic in a chiller bag.