Combine first 8 ingredients in large bowl and whisk together
Add the cubed lamb and massage the marinade into the meat. Cover and place in refrigerator for 2-8 hours
Combine all liquid relish ingredients in a bowl and whisk together. Add in tomatoes and mint and mix thoroughly.
Thread Lamb onto Skewers or sticks. Intersperse some pieces with some fat to help keep the meat moist and basted while cooking.
Fire up the grill to 'High' and preheat. If you have temp control we want to be around 450 degrees for this. If no control hold your hand about 2 inches above the surface of the grill. If you can't slowly count past three without having to pull back your hand - the grill is ready!
wrap pita bread in foil and warm in oven or on upper rack of BBQ
Add lamb skewers the grill - cook about 3 mins then make a 1/4 turn rotation of your skewer - so about 12 mins total cook time for medium
Remove lamb from skewers and serve with Pita bread and tomato-mint relish.