Yes, you can. I use freezer safe plastic containers or freezer bags to freeze the keema. To re-heat, tip the frozen keema into a medium sized pan. Similar to how you would take out ice cubes from an ice-cube tray. Add ½ cup water, and heat till it comes to a boil. Turn heat to simmer, and cook for a few minutes till warmed through.   Keep in mind that potatoes can get mushy when frozen.  Make the keema as per the recipe, and then add par-boiled potatoes when warming it up.