Ina 6 quart pot or Dutch oven, on medium heat, partially cover and boil the lentils with the turmeric and salt till almost tender (approximately 30 minutes).
Add the Sambar masala powder (careful as it packs some heat) and the coriander, and chili powder.
Lower the heat and let simmer for 5 minutes.
Add sliced onions and continue to simmer covered for another 5 minutes.
If you would like to add beans, 4-6 oz, or a cup of drumsticks, you could do so at this point and simmer until the vegetables are nearly done.
Now add a tablespoon of tamarind paste and continue to simmer for another 10 minutes until the dal is fully cooked, and the grains blended.
Check for tanginess, as the tartness of tamarind varies depending on the brand name you use. If you want more of a tang, then add a little more tamarind at a time till it hits your taste buds!
If you find the dal is getting too thick anytime during the cooking process, you can thin it down with hot water. Remember, you want a nice texture to the dal, not runny. Set aside.