1.Make chilli tomato sauce, Heat oil in medium frying pan; cook onion and garlic, stirring, until onion softens. Add remaining ingredients; bring to the boil. Reduce heat; simmer, uncovered, about 5 minutes or until sauce thickens slightly. Blend or process sauce until smooth.
2.Meanwhile, thread lamb onto skewers.Combine yogurt, juice, garlic and thyme in small bowl. Place two-thirds of the yogurt mixture into separate bowl; reserve. Use remaining yogurt mixture to brush lamb.
3.Cook lamb skewers, in batches, on heated oiled grill plate (or grill or barbecue) until browned all over and cooked as desired.
4.Serve kebabs with reserved yogurt mixture, chilli tomato sauce and mesclun.
You can also use boned-out leg of lamb, cut into cubes. Use poblano, pasilla or anaheim chillies if you can find them. Green capsicums (bell pepper) are too sweet for this recipe, but long green thai chillies provide the right heat. You need eight bamboo skewers for this recipe. Soak them in cold water for an hour before using to prevent them from splintering or scorching. Serve with warmed pitta bread.