- Grind all the ingredients under 1st marinade without adding any water. 
- Grind all the ingredients under 2nd marinade to make a thick paste. Do not add any water. 
- Marinate the lamb pieces along with the diced onions in the 1st marinade and keep for 1 hour. 
- Squeeze out the excess moisture if any and marinate the lamb and onion in the 2nd marinade and keep for 2 hours. 
- Pierce the lamb pieces and onions onto wet bamboo skewers. You can either insert the onion pieces between each piece of lamb or at the ends like I have done. 
- Grill till the lamb is cooked well and tender. If you think it is getting dry, baste using melted butter. 
- Serve hot with a sprinkle of chat masala and lemon wedges. I added a side salad and mint-coriander chutney which went well with the lamb skewers.