Wash the lentils well, and then put them into a sauce pan. Add 4 - 6 cups of salted water to cover the lentils.
Bring lentils to a boil then reduce heat, cover and allow to simmer until they are soft. Keep the water level above the lentils.
While the lentils are simmering, grind the spices together then toast them over low heat in a dry sauté pan until you have released their aromas. Set spices aside.
Using the same sauté pan, heat ghee or oil over low to medium heat. Add onions and sauté until they are soft. Add garlic, sauté another 3-4 minutes. Do not burn the onions or garlic. Add spice mixture; continue to cook for 2 minutes.
Once the lentils have become soft, add them and their cooking liquid to the onion and spice mixture (add more water or broth if lentil are too thick). Stir and scrape up any bit from the bottom. Stir in lemon juice, adjust salt and continue to cook for 5 minutes.
Just before serving add yogurt and heat through. Serve with a wheat flat bread such as roti.