Kitcheri is unique because it falls under both the neutral and medicinal categories. It provides nourishment, and due to the spice combination, also benefits digestion.
Combine both lentils and rice in a medium bowl. Rinse thoroughly a few times and drain out the water.
Put drained lentils/rice and water into a stainless steel cooking pot with lid. Add salt and turmeric. Bring to a boil on medium high heat, reduce heat to simmer and cook for 20 minutes. (Be careful not to cover the pot completely to avoid the kitcheri from boiling over.) Turn off heat.
Meanwhile, heat the ghee or oil on medium heat in a saucepan. Sauté the mustard seeds and cumin seeds until the mustard seeds begin to pop. Add ginger and onion and sauté for 5 to 6 minutes. Add tomato, cook for another few minutes until the tomato breaks down completely.
Add the masala mixture to the porridge. Stir in garam masala and fresh cilantro. Serve hot with a squeeze of fresh lime if you like.
*You may have to experiment with how much water you use to find a consistency that you like. (The more water, the thinner the consistency). A thinner consistency is preferable if digestion is weak. You will notice that kitcheri will thicken after it cools.