Fishcakes show how mashed potato can be used as a binder. Once you understand that potato plus protein plus egg holds together and fries well, you can adapt this with different ingredients and leftovers.
Peel and chop 600 g potatoes into even chunks.
Place in a saucepan, cover with water, add a pinch of salt and bring to the boil. Simmer for 15–20 minutes until soft.
Drain and mash until smooth. Allow to cool slightly.
Add the drained tuna, sweetcorn and 1 egg to the mashed potato.
Season with salt and black pepper and mix until fully combined.
Divide into 5 portions and shape into even rounds.
Heat 2 tbsp sunflower oil in a frying pan over medium heat.
Fry the fishcakes for 4–5 minutes on each side until golden and heated through.