Halve the kiwi and scoop the flesh into a small bowl; mash well with a fork until smooth.
Add the mashed kiwi and remaining ingredients in a large ziptop bag to marinate. Leave at room temperature for about 20 min, no longer than 1 hour. (Kiwi acts as a tenderizer and if mixed with meat for several hours can make it too soft.).
Drain the lamb and thread onto skewers that have been soaking in water.
Grill on high heat for 5-7 min, turning skewers to brown the lamb on all sides. Do not over cook.