In your pressure cooker, dump the meat and soaked lentils along with all the whole spices. Pressure cook on high for 12 mins. If using a traditional pressure cooker, cook till 7-9 whistles.
Remove the cardamom and cinnamon sticks, and dump the mixture in a non-stick wok or cast iron wok. Saute on medium heat until the mixture is completely dry. This step is crucial to remove the moisture. When the mixture is totally dry, the kebab will be dry and crumbly but hold together when pinched between fingers.
Dump the dry meat mixture in your food processor along with the onion, cilantro and mint. Pulse for a few seconds in bursts, and then pour in the beaten egg very slowly through the nozzle. Only pulse till the kebabs come together. Shape in patties, the size depends on your preference.
To fry, dip the kebab in beaten egg, and shallow fry in oil on medium high heat till deep brown in color. Allow the kebabs to fry undisturbed for a few minutes on each side. The total cooking time will be around 7-9 mins depending on the heat.
Sandwich the kebab between two savory buns with tamarind and cilantro chutney or enjoy as is!