Cut the potatoes into fries, place on a baking tray and drizzle with olive oil, salt and pepper. Bake for 25-30 minutes until cooked through and crispy.
Finely chop the red cabbage and iceberg lettuce. Pick the herbs to have full leaves.
Prepare to roll the rice paper: Dip the rice paper in room temperature water for a few seconds, then lay out on a damp kitchen towel.
Place all the ingredients (choose chicken or prawns each time) in the lower third of the rice paper (the third closest to you). Stack ingredients on top of each other, leaving at least 2-3 cm clear of fillings on all edges.
Wrapping a rice paper roll is much like rolling up a burrito. Start by picking up the rice paper wrapper from the end closest to you, pulling it over the fillings to enclose them.
Fold both sides in towards the centre, then complete by rolling the whole roll away from you. You should end up with a log type shape with the filling completely enclosed.
Keep the rolls under a damp cloth.
To make the sauce: Mix the peanut butter, soy sauce, rice vinegar and sriracha together.