Place a pot of water to boil on medium-high heat. Add potatoes and boil for 20 minutes. Drain and wash under cold water, then peel. If potatoes are cooked enough, the skins will peel off easily. Pierce potatoes all over with a toothpick/skewer. Rub on some Red Chilli, Turmeric and Salt. Fry in hot oil until golden brown all over, then remove and set aside.
Roast Green Cardamom, Bay Leaf, Cinnamon Stick, Cloves and Green Chillies in oil till fragrant. (30 seconds).
Add Cashews and cook for 2 - 3 minutes.
Add Onions and cook till golden brown. 10 - 15 minutes. Allow to cool if needed (depends on the blender). Then blend and set aside.
Add paste back to pot with ginger and garlic. Cook for 2 minutes.
Add Red Chilli Powder, Turmeric Powder, Coriander Powder, Cumin Powder and Fennel Powder. Cook for 5 - 6 minutes.
Add pureed tomatoes. Cook for 8 - 10 minutes.
Turn heat right down. Stir in the whisked Yoghurt. Cook on high or 2 - 3 minutes and add Water.
Add Garam Masala, Salt, Sugar, Cream and Kasuri Methi. Simmer for 2 minutes.
Add Potatoes. Simmer for 5 - 10 minutes on low. Top with Coriander and serve.