Begin the night before soaking the lentils and beans for 5 hours. Drain.

Begin the cooking by adding all the beans and lentils to the pressure cooker. Add the garlic, ginger and spices and 3 cups of water. Mix well and turn on your pressure cooker to high and set for 1 hour.

In a pot of boiling water, add the tomatoes and cook for approximately 5 minutes. Once cool, peel the outer skin. Then, using the large side of a cheese grater, grate the tomatoes. Set aside.

In a pan, melt the butter on medium heat. Once melted, add the cumin seeds and cook for 1 minute. Next, add in the onions and soften for about 5 minutes. Now, add in the grated tomatoes and cook for 3 - 4 minutes. Finish, by adding in the serrano and cook for 1 minute.

Add the cooked beans and lentils to a pot. Add 3 cups of water and turn on to medium heat. The beans will simmer for 2 hours. Add the onions and tomato mixture after the first 30 minutes of cooking. Then, add the spices and butter about an hour in to the cooking. Keep your eye on the pot. You want enough water to make a gravy. If the water has cooked off, add a cup at a time.

An optional final step is to drop in yogurt. Serve with white rice. Enjoy!