Preheat the oven to 200C Fan.
Lay out a large sheet of tin foil, then lay a piece of baking paper over the top.
Add the cooked rice & quinoa almost in the middle, but slightly closer to you.
Lay over the asparagus, cherry tomatoes, salmon, and king prawns.
Season with salt and pepper, then lay two ‘half-moon’ slices of lemon over the top of the salmon.
Fold the foil and baking paper over to cover the salmon, then fold the edges over to create a giant ‘Cornish pastie’. Leave some space between the food and the folded edges so that it can puff up when it steams.
Before you completely seal it, pour in the water, this will help it steam.
Place it in the oven for 15 minutes. Once cooked, cut it open and sprinkle over the chopped parsley and add the zest of ½ a lemon. Be careful as you open it as there will be a lot of steam.