Martha's salmon en papillote with miso, lime & ginger

1. To make the marinade, stir together the miso paste, soy sauce, mirin, lime zest and juice in a medium-sized bowl. Grate in the ginger. Add the salmon, cover and leave to marinate in the fridge for at least 1 hour or, better still, overnight.

2. Preheat the oven to 180°C, gas mark 4. Cut two large rectangles of baking parchment and lay each out on the work surface. Place the marinated salmon on the parchment , top the fillet with a sprinkle of sea salt and a handful of salad onions.

3. Fold the empty half of the parchment paper over the salmon and crimp the edges closed, as if making a square pasty. Repeat with the second piece of salmon, then put the parcels onto a baking tray.

4. Bake for 30-35 minutes. The salmon should be tender and cooked through. Serve in the parcel, so none of the juices are lost, or transfer to plates and drizzle over the juices.