Preheat the oven to Gas Mark 7
Lay out a square of foil big enough to pop everything in and seal up. About 1.5 times your dinner plate.
Place a selection of veggies and potatoes on the foil, top with the fish and spread 1 tsp pesto on top.
Fold the foil parcel up so everything is covered and pop onto a baking tray.
Bake for 20 minutes