Cook the gnocchi in boiling salted water following pack instructions, then drain well.
Heat the double cream in a pan, then stir in the parmesan and lemon juice. Let it bubble up then take off the heat, add the crab, parsley and gnocchi. Tip into a small baking dish and sprinkle over a little more cheese. Put under a hot grill for 2-3 minutes until golden and bubbling. Serve with salad.