Place the peeled and chopped potatoes into a pan of boiling water and cook on a medium heat for approx 20 minutes, or until soft enough to stick a fork through.
Once the potatoes are tender, drain and mash them thoroughly.
Transfer the mashed potato to a large mixing bowl and add all remaining filling ingredients. Mix together well until everything is nicely incorporated.
Shape handfuls of the mixture to form your fishcakes. Make sure to let the mixture cool a little first if the potato is still hot. The recipe should make approx 6 fishcakes (3 servings if having 2 per person).
Set out three bowls and a plate. Add the gluten-free flour to the first bowl, the beaten egg to the second and the gluten-free breadcrumbs to the third.
Coat each fishcake first in flour, then egg, then breadcrumbs, before placing on the plate.
Heat the vegetable oil in a large frying pan over a medium heat. There should be enough oil to fully cover the bottom of the pan by a few millimetres. Make sure the oil is nice and hot before adding the fishcakes, or they may become a little soggy. The fishcakes should sizzle as they hit the pan.
Fry the fishcakes for a few minutes on each side, or until the breadcrumbs are golden brown and crisp. You can also use tongs to hold the cakes sideways, rotating slowly to make sure the edges get a good browning too.
Once fried, transfer to a plate lined with some kitchen roll to soak up some of the excess oil.
Serve with your favourite dipping sauce (garlic mayo, tartare or sweet chilli sauce are great), fresh salad, chips or whatever you fancy!