Pressure cook ½ cup of moong dal and ½ cup of basmati rice with 3 cups of water for 3 whistles and let the pressure release naturally.
Boil water in a large pot, blanch 2-3 cups of spinach for 1-2 minutes until wilted, then transfer to ice-cold water to retain its green color. Blend the blanched spinach (without adding water) to make a puree. Keep it aside.
Heat ghee in pan, and add whole spices like cinnamon, cardamom, cloves, cumin (jeera), minced ginger garlic, and green chilies. Saute for a few seconds.
Then add onions and saute until they are light brown in color. Next, add tomatoes and cook till they are soft.
Add blanched palak puree and cook for another 1 minute.
Lastly, add cooked moong dal and rice mixture, salt, garam masala, and ½ cup of hot water (if required). Mix well. Cook for 2-3 minutes until it comes to a boil.
Lastly, add the extra tadka (optional) to the palak khichdi, and mix well. Delicious palak khichdi is ready to be served.