Place the chopped chicken, red curry paste, egg, fish sauce, sugar, and cornstarch into a food processor.

Pulse the mixture until it becomes a sticky, smooth paste, ensuring the chicken is fully minced and ingredients are well combined.

Transfer the paste to a mixing bowl and stir in the sliced green beans and shredded kaffir lime leaves until evenly distributed.

Moisten your hands with a little water to prevent sticking, then shape the mixture into small, flat patties about 2 inches in diameter.

Heat about 1 inch of vegetable oil in a frying pan over medium-high heat until it reaches 350°F (175°C).

Carefully place the patties into the hot oil in batches, frying for 3-4 minutes on each side until they are golden brown and cooked through.

Remove the cakes from the pan and drain them on a wire rack or paper towels to remove excess oil.

Serve the warm Thai chicken cakes immediately with a side of sweet chili sauce for dipping and a garnish of cucumber slices if desired.