Pressure cook the dal adding 3 cups of water for 3-4 whistles.
Heat oil or ghee in a Kadai and add the cumin and let them splutter.
Then add asafetida, minced ginger-garlic, chopped green chili, curry leaves, and saute for a few seconds.
Next, add the onions and saute till the onions turn light brown in color.
Add tomatoes and cook till tomatoes turn soft, takes 2-3 minutes.
Add all the spice powders – turmeric, red chili powder, coriander powder, or garam masala powder and fry for a minute.
Now add the cooked and mashed dal, stir well. Add water to adjust consistency and salt to taste.
Boil dal for 2-3 minutes on a medium-low flame. Finally, garnish with chopped coriander leaves.
Dal Tadka is ready, add extra tempering (tadka) and serve hot.