South Indian Tomato and Tamarind Soup With Pigeon Peas (Toor Dal Rasam)

November 27, 2018 Updated: November 27, 2018

South Indian Tomato and Tamarind Soup With Pigeon Peas (Toor Dal Rasam)

Rasam is a thin, tart, and spicy South Indian soup that is traditionally eaten with plain rice or savored after a meal on its own. I like it for breakfast as a savory and healthy start to my day. The combination of tamarind, black pepper, tomatoes, and lemon juice makes this a healing and healthy nutrient-dense snack or meal.

Slow Cooker Size: 5-quart
Cooking Time: 7 hours on high

Makes 16 cups

For slow cooker:

  • 5 large tomatoes, peeled and coarsely chopped
  • 3/4 cup duhli toor dal (dried, split, and skinned pigeon peas), picked over and washed
  • 6 cloves garlic, minced
  • 2 tablespoons tamarind paste
  • 2 teaspoons whole black peppercorns
  • 4 whole dried red chilies, broken into pieces
  • 3 tablespoons rasam powder (recipe follows)
  • 1 tablespoon plus 2 teaspoons sea salt
  • 1 teaspoon turmeric powder
  • 1 teaspoon red chili powder or cayenne pepper
  • 7 cups water

For tarka (tempering): 

  • 2 tablespoons ghee or oil
  • 2 pinches hing (asafetida)
  • 1 teaspoon cumin seeds
  • 1/2 teaspoon black mustard seeds
  • 4 whole dried red chilies, broken into pieces
  • 10–15 fresh curry leaves

For serving:

  • Juice of 1 medium lemon
  • 2 tablespoons chopped fresh cilantro

Put the tomatoes, dal, garlic, tamarind, peppercorns, red chilies, rasam powder, salt, turmeric, red chili powder, and water in the slow cooker. Cook on high for 7 hours.

Blend with an immersion blender or in batches in a blender until smooth. Leave the mixture in the slow cooker until the tarka is ready.

In a separate frying pan make your tarka. Heat the oil or ghee over medium-high heat. Add the hing, cumin, mustard, and red chilies and cook until the mixture sizzles, about 30 seconds. Add the curry leaves and cook until the leaves turn slightly brown and begin to curl. (Be careful—the seeds and leaves may pop out, so keep a lid handy to briefly cover your pan.) Mix occasionally so the spices don’t burn. After 1 to 2 minutes, put the hot tarka mixture into the slow cooker.

Add the lemon juice and cilantro. Mix well and serve hot. There is no need to remove any spices—they can all be consumed, including the red chiles. I love serving this soup in short glasses garnished with grated lemon zest for parties.

Notes: Use a serrated peeler to most easily peel tomatoes, or peel them traditionally by blanching: Cut an X into the non-stem end of each tomato with a sharp knife. Drop them into boiling water for a little less than a minute, until the peel starts to pull away. Pull the tomatoes out of the water using tongs, drop them in an ice bath, and once they’ve cooled, they will peel easily. You can also make this soup without peeling, but this extra step will make for a smoother consistency.

Tamarind is key to this dish. I used paste because it’s easier to find. You can also replace the paste with 1 cup of tamarind water. To make it, soak about a 2-inch cube of dried tamarind pulp in 1 cup boiling water. Strain the water, discard the pulp, and add the tamarind water to your slow cooker.

If you don’t have rasam powder, substitute 2 tablespoons coriander seeds, 1 tablespoon cumin seeds, 1 teaspoon whole black peppercorns, and 2 teaspoons fenugreek seeds. Add these ingredients to your slow cooker before cooking.

To make this dish in a 3 1/2-quart slow cooker, use 1/4 cup toor dal, 3 large tomatoes, and 4 1/2 cups water. Cut the other ingredients in half and proceed with the recipe, cooking on high for 4 hours. A half recipe makes 10 cups.

Rasam Powder

Many South Indian meals start with a small bowl of thin, spicy tomato soup called rasam. This is the flavorful spice blend that is used to make the delicious and nutritious soup by the same name. You can use it for soup or use it to make a quick Indian-inspired dish.

Makes 3 cups

  • 1 heaping tablespoon chana dal
  • 1 heaping tablespoon skinned and split toor dal
  • 2 cups coriander seeds
  • 1/2 cup cumin seeds
  • 1/2 cup whole black peppercorns
  • 1/2 teaspoon fenugreek seeds
  • 10 whole dried red chilies, broken in pieces
  • 15 fresh curry leaves, coarsely chopped
  • 1 teaspoon turmeric powder

In a shallow, heavy pan, dry roast all the ingredients except the turmeric over medium heat. When putting them into the pan, start with the lentils so they are closest to the heat and cook through. Shake or mix frequently, and watch closely that the mixture does not burn. Once the lentils brown, the curry leaves start to curl up, and the spices smell aromatic (about 4 minutes), transfer the mixture to a large plate or bowl and allow it to cool for 15 minutes.

Once the mixture is cool, add the turmeric and transfer to a spice grinder or the dry jug of a powerful blender, such as a Vitamix. You may need to grind it in small batches, depending on the size of your grinder. Sift after grinding to get a finer powder. Store in an airtight container for up to 6 months.

Reprinted with permission from “The Indian Slow Cooker, Second Edition” by Anupy Singla. Published by Agate Surrey, November 2018.