Add some oil to a wok. Once it has heated, fry the potatoes on medium heat till they get brown, and set it aside for later use.
Heat oil in a skillet, and add bay leaves, black and green cardamom, cinnamon stick, black peppercorns, as well as cloves, and give a stir.
Add cumin, and let it crackle. Add cashew nuts, and sliced onions and saute till the onions get brown, then add ginger garlic paste and give it a stir.
Pour a dash of water into the pan, and add turmeric powder, red chilli powder, coriander powder, cumin powder, and saute it. You can also add green chilli at this stage.
Beaten yogurt is to be added to the spice mixture, and continuously give it a stir so that it does not split and give it a boil. Add salt, and reduce the curd, till the oil separates.
Turn off the gas, and let the mixture cool down. Remove the ground spices before finely grinding them into a paste.
On high heat, pour the paste into the pan, and add some water for consistency. Then add the fried potatoes to the gravy and stir nicely.
Finally, garnish it with fenugreek leaves, coriander sprig, and a dollop of cream. Add a pinch of sugar too, to balance out the flavor of the dish.
Your Dum aloo is ready to serve.