Oh, this was so good. So simple but so good.
What you need:
1 pitta bread
four fish fingers
three leaves of cos lettuce (or equivalent in salad leaves)
tomato, sliced (one to four depending on size)
Pop the fish fingers in the oven to bake as per the instructions.
While they are cooking, cut right round the pitta and open out. Spread a little mayo over the inside of both pieces.
Lay the leaves along one side.
When the fish fingers are cooked, lay them on top of the lettuce/leaves, add the sliced tomato and top with the other pitta half (season if you want - I didn;t as fish fingers and mayo are already seasoned).
Eat straight away!