Heat 3 tablespoons of the oil in a frying pan, add the onion and fry for 4 minutes. Add the chilli flakes, garlic and curry paste and fry for 1 minute.
Transfer to a food processor or blender with the beans, ground almonds, salted almonds, egg and a little salt and pepper and process until the mixture starts to bind together.
Using lightly floured hands, take about one-eighth of the mixture and mould it around a metal skewer, forming it into a sausage about 2.5 cm (1 inch) thick. Make 7 more koftas in the same way. Cover and chill until required.
Mix together the yogurt and mint in a small serving bowl and season to taste with salt and pepper. In a separate bowl, mix together 2 tablespoons oil, lemon juice and a little salt and pepper. Cover both bowls and chill until required.
When ready to serve, place the koftas on a foil-lined grill rack and brush with 1 tablespoon of oil. Cook under a preheated moderate grill for about 5 minutes until golden, turning once. Brush the koftas with the lemon dressing and serve in warm naan breads, drizzled with the yogurt dressing.