First heat 1/2 tsp of oil in skillet and fry the sliced onion untill rawness gone.Keep aside.
Wash and keep keema / minced meat on a colonder to take off extra water.and spread on a paper napkin.
Now take a big bowl(preferably salad mixing bowl),mix all the ingredients and knead them very well using half spoon of oil. Be careful it should not be watery as that will break while grilling or baking the kebabs.Keep the mixture aside.
Make balls from that mixture and then take little water on your palm and wrap these balls on a skewer to give nice kebab shape upto 4-5 inch length.
Now preheat oven at 400'F and then place the skewer on a baking tray and keep inside the oven for 10mins at 300'F. Then brush or sprinkle rest of oil on kebabs and turn the skewer and keep for another 10-15mins.
Now take out and serve hot sprinkling lime juice and chaat masala with salads.
Here kneading all the ingredients is very important or kebabs wont come smooth and juicy.I used mixer to mix all the ingredients and then knead them well. Again I must say check the spice level and your oven temperature as it varies .So first time keep an eye while baking to avoid burning and tough dry kebabs.