To begin, wash the toor dal thoroughly and pressure cook it with 2 cups of water and a pinch of turmeric powder until it becomes soft. Once cooked, mash the dal with a ladle until smooth. Set aside.

Soak the tamarind pulp in half a cup of warm water for about 10 minutes. After soaking, strain and extract the tamarind juice by pressing the pulp. Discard any seeds or fibres, and keep the tamarind water ready for later.

Heat 1 tablespoon of vegetable oil in a deep pan over medium heat. Add mustard seeds and let them crackle. Then, add fenugreek seeds, dried red chilies, and curry leaves. Sauté for about 30 seconds until the spices release their aroma.

Add the sliced onions and a pinch of asafoetida to the pan. Cook the onions until they become soft and translucent, stirring occasionally.

Next, add the chopped carrots, eggplant, tomato, and drumstick pieces (if using). Stir well and sauté for 3-4 minutes. Then, pour in the tamarind water and bring it to a gentle simmer. Allow the vegetables to cook for 5-7 minutes until they soften.

Stir in the sambar powder, salt, and turmeric powder. Mix well to coat the vegetables with the spices. Add 1 to 1.5 cups of water, depending on the desired consistency of the sambar.

Once the vegetables are cooked and the flavors have combined, add the mashed toor dal to the pan. Mix well and simmer the sambar for an additional 10 minutes. Taste and adjust the salt or spices as needed.

To serve, ladle the hot sambar into bowls and garnish with fresh coriander leaves. Pair the sambar with steamed rice or idli for an authentic Indian meal. For added flavour, drizzle a spoonful of ghee over the sambar before serving.