Make the sweet chili dipping sauce: combine sugar, rice vinegar, water, and salt in a small saucepan over medium heat. Stir until sugar dissolves, then simmer for 5 minutes until slightly thickened. Remove from heat, stir in chopped chili, garlic, cucumber, and peanuts. Set aside to cool.

Add the chopped fish to a food processor and pulse until it forms a thick, sticky paste. Do not over-process; some texture should remain.

Transfer the fish paste to a mixing bowl. Add red curry paste, egg, fish sauce, cornstarch, and sugar. Mix thoroughly until well combined.

Fold in the finely sliced green beans, shredded kaffir lime leaves, and chopped coriander. Mix until evenly distributed.

With wet hands, shape the mixture into 12 small patties, about 6cm wide and 1cm thick.

Heat vegetable oil in a large frying pan or wok over medium-high heat until it reaches approximately 180°C (350°F).

Fry the fish cakes in batches of 4-5, cooking for 3-4 minutes per side until deeply golden brown and cooked through to an internal temperature of at least 63°C (145°F). The fish cakes should be firm to the touch.

Transfer cooked fish cakes to a plate lined with paper towels to drain excess oil.

Serve the crispy fish cakes warm with the sweet chili dipping sauce on the side, garnished with fresh coriander leaves and lime wedges.