Wash toor dal and soak for 30 minutes. Place in pressure cooker along with potatoes, tomatoes, onions, green chilies, sambar powder, crushed ginger, turmeric, cayenne pepper and salt.

Add enough water to cover. Stir, cover and cook until pressure cooker begins to steam.

In a skillet, heat coconut oil. Add eggplant and brown lightly. Add green peppers and sauté for a few minutes. Set aside.

Remove cover of pressure cooker and mash the potatoes and onions. Add eggplant mixture, coriander leaves, fenugreek and hing.

Cover pressure cooker and resume cooking for another 5 minutes.

Heat a little coconut oil, along with mustard seeds, cumin seeds, chilies, and curry leaves in skillet until fragrant.

Add to potato mixture and cook an additional 5 minutes. Let stand to marinate flavors until ready to serve. Serve with idli.