Mix the yogurt with the curry paste in a large bowl. Add the chicken, season, then stir really well. Cover and leave for 30 minutes at room temperature to give the spices time to flavour the chicken (or make ahead and chill for several hours or overnight).
Make the salad before you start to cook the kebabs. Simply mix together the cucumber, tomatoes, chilli, onion and coriander. Season lightly, then cover until you’re ready to serve with the meal.
Preheat the grill or barbecue. Push the chicken onto 8 metal or wooden skewers. Grill or barbecue the kebabs for 8-10 minutes, turning them frequently. At the same time, warm the tortillas or chapatis on one side of the barbecue, wrapping them in foil. Serve two kebabs per person, with two tortillas or chapatis and plenty of salad.