Rinse the sabudana under running water until the water runs clear, then cover with water at a 1:1 level in a bowl and let it soak for 4 hours, or until each pearl turns soft and translucent when pressed between your fingers.

Place the whole potatoes in a saucepan of water and bring to a boil, then let them cook until a knife slides in easily.

Drain the boiled potatoes, let them cool enough to handle, then peel and cut them into small even cubes.

Dry roast the peanuts in a pan over medium heat, stirring constantly, until the skins darken slightly and the peanuts smell nutty and toasted.

Let the roasted peanuts cool slightly, then coarsely crush them in a mortar and pestle or a food processor, leaving some texture rather than a fine powder.

Tip the soaked sabudana into a strainer and let any excess water drain off completely for a couple of minutes so the pearls stay separate when cooked.

Heat the ghee in a kadai over medium heat, add the cumin seeds and let them sizzle, then add the curry leaves and chopped green chili and sauté for a few seconds until fragrant.

Add the cubed boiled potatoes to the tempering and sauté gently for a few minutes until they pick up a light golden color at the edges.

Add the drained sabudana, crushed peanuts, rock salt, and sugar to the pan, then toss gently and cook over low heat until the sabudana pearls turn glossy and translucent throughout.

Turn off the heat, squeeze the fresh lemon juice over the khichdi, and scatter the chopped coriander leaves on top before serving hot.