The yogurt in the marinade tenderizes the meat and imparts a delicious tangy flavor that complements the zippy garlic and smoky char of the meat.
Mix together the marinade ingredients (yogurt through black pepper or optional pepper flakes) in a glass bowl or zip top bag.
Add the kabob cubes to the marinade, cover bowl or seal bag, and refrigerate for 8-24 hours, stirring or turning the bag occasionally.
Remove the meat from the marinade and string on 4 skewers. Discard the marinade.
Grill over direct high heat for 8-12 minutes or until desired degree of done-ness.
Serving suggestion: Serve with grilled pita bread, tzatziki sauce, and grilled peppers and onions.