Fry the onion, chilli, garlic, and ginger in vegetable oil for five minutes until softened.
Add the curry paste and cook for an additional five minutes.
Stir in the prawns and vinegar, cook for five minutes, then remove from heat.
Fry the second onion with chilli and mustard seeds for five minutes in a separate pan.
Mix in the mashed potato, turmeric, coriander, and peas until combined.
Cool the mixture, then roll and flatten 75g portions into fritters.
Whisk chickpea flour, rice flour, cayenne, seasoning, and 90ml of water to form a batter.
Heat deep-frying oil in a heavy pan until a breadcrumb sizzles instantly.
Dip the potato fritters into the batter and deep-fry for three minutes until golden.
Stir cream into the prawn curry, warm through, and serve with the hot fritters.