Preheat oven to 200°C/400°F.
Cut four large pieces of aluminum foil or parchment paper (if you’re using thin parchment, double it up).
Divide the vegetables and lay them in the center of each piece of foil/paper – carrots at the bottom, then broccolini, then the beans. Try to lay them fairly evenly.
1 bunch baby carrots, 1 bunch baby broccoli, 1/2 lb green beans, 2 scallions
Place the fish on top of the vegetables, then top each piece with the thickly sliced scallions. Season with a small amount of salt, then fold the foil/paper to make tightly sealed parcels. Just before you seal the parcels closed, add 2 tsp water to each one to help the food steam inside. If you’re using paper you may want to tie string around the outside to stop it unfolding.
1 1/4 lb white fish fillets
Place the parcels onto a baking tray and cook for 15 minutes.
While the parcels are cooking, make the dressing. Mix together the extra scallions, ginger, miso paste, vinegar and sesame oil. Season to taste with salt and pepper, and set aside until you’re ready to use.
1 scallion, 1 inch ginger, 2 tsp white miso paste, 1/4 cup rice wine vinegar
When the parcels are done, place each one onto a serving plate with a scoop of rice (or crispy rice as noted above). I like to let everyone open their own parcel at the table, however you could open them before serving and carefully slide the contents onto each plate. Spoon over the dressing and eat immediately.