Fry the onion in a large pan with a bit of oil. Add the mince. Mix till it changes it's color to ashy, then add the potato cubes and half a cup of boiling water. Wait for the water to evaporate and the potatoes to soften. Take off the stove.

When the potatoes are ready and there's little to no water in the tray, put the mix over. Be careful, if there's still water there, it won't look as good.

Put in the oven again and wait until golden.