To make the sauce, stir together the yogurt, tahini, lemon juice, garlic and salt; taste and adjust as you like it. If possible, make it up to a day or two in advance to allow the flavours to blend.
To make the kofta, mix all the ingredients together gently with your hands. Soak about 8 bamboo skewers in water for at least 10 minutes. Shape a small handful of the meat mixture around the end of each stick (you could even fit two per stick). Preheat your grill to medium and grill the kofta, turning them often, for 8-10 minutes, or until they’re cooked through. Serve warm, with the yogurt sauce and warm flatbread. Serves 6.