Cut the peeled potato in half and boil for seven minutes.
Drain the potato and set aside to cool.
Fry the onion, ginger, garlic, and chilli in olive oil until soft.
Add sugar and vinegar, then boil for 6 minutes.
Add tomatoes and simmer for five minutes until syrupy.
Stir in the chopped mint and set the chutney aside.
Grate the potato and beetroot into a bowl.
Combine with curry powder, spring onions, and seasoning.
Form the mixture into four flattened cake shapes.
Fry cakes in vegetable oil for three minutes per side.
Serve hash cakes topped with mackerel, a poached egg, and chutney.