In a large glass or ceramic bowl, mix the yoghurt, vinegar, and garlic. Season with salt and pepper to taste. Add the lamb cubes and stir to coat all pieces. Cover and marinate for about 2 hours at room temperature, stirring occasionally.

Thread the lamb onto skewers, alternating with chunks of the bell peppers and mushrooms, leaving space between pieces so meat cooks evenly. Discard marinade.

Grill skewers over direct high heat for 5 to 6 minutes, until lamb is medium rare. Serve with pita bread and Raita.

Makes 4 to 6 servings.