Wash the lentils under running water for a couple of times and let it soak with water for 30 mins to ensure faster cooking and better digestion.
Meanwhile chop the onion, tomato, green chilli. In a pan add 2-3 tbsp oil and warm it up. Add ½ tsp cumin seeds and let it sizzle for a few seconds, follow this with chopped onion. Cook it for 5 mins on medium flame, till you see onions turn golden brown.
Add 1 tsp of salt and turmeric powder and mix well.
Add the ginger garlic paste and green chilli to the pan and cook it for 2-3 more minutes.
Now add the red chilli powder, coriander powder and cumin powder and stir well. Keep cooking it on a medium flame for 2 more minutes and then add the chopped tomato. Cook the tomatoes for 5 more mins and they will start turning soft.
Add the soaked lentils to the pan without the water used for soaking. Mix everything well. Add 240 ml water to the pan and increase the flame. Bring it to a boil and let it boil for a minute. Lower the heat, cover the pan and let it cook on a medium to low heat for 20 mins. Check on it occasionally and give it a stir.
After 20 - 25 mins, you will see the lentils have cooked really well and have thickened. Add the garam masala to the pan and mix well. Add 240 ml water to give a thinner consistency to the daal. Let it simmer without the pan cover.
Meanwhile grab another tiny pan for the tempering. In the pan add remaining oil, and once warm enough add the cumin seeds, asafoetida and curry leaves. Follow it up within a min with dried red chilli and some chilli powder (both optional). This step should take 3 mins and add this to the daal.
Give it a good mix. Check for seasoning and add salt if needed. Add 1 tsp sugar and some fresh coriander leaves.
Serve this with steamed rice or chapati (page xxx) and with a squeeze of fresh lime or lemon. Enjoy!