½ or ⅔cuppigeon pea lentils(tuvar dal or arhar dal)
1teaspoonblack mustard seeds
½teaspoonsplit and skinned black gram(urad dal) - optional
1 or 2dry red chilies
1pinchasafoetida(hing)
¼teaspoonturmeric powder
1 to 2cupswateror add as required
1tablespoonseedless tamarind soaked in ½ cup water
10 to 12curry leaves
2tablespoonoil
salt as required
2 to 3tablespoonscoriander leaves
For dry roasting and then grinding to semi coarse or fine powder
2 to 3dry red chilies
8 to 10fenugreek seeds
½teaspoonblack peppercorns
1teaspooncumin seeds
2teaspooncoriander seeds
Instructions
Preparation
First take all the whole spices meant to make the rasam powder.
On a low heat, dry roast the spices stirring often till they are fragrant and golden. Ensure that the spices don’t get burnt. Once roasted well then remove the spices in a plate and let them cool at room temperature.
Once they are cooled, in a dry grinder or coffee grinder, grind these spices to a semi coarse or fine powder. Keep aside.
Soak 1 tablespoon seedless tamarind in ½ cup of hot water for 20 minutes. Later squeeze the tamarind pulp and keep aside.
In a 2 litre stovetop pressure cooker, cook ½ to ⅓ cup arhar dal (pigeon pea lentils) with 1.5 cups water for 7 to 9 minutes or till they are completely soft and mashable.
With a spoon or wired whisk, mash the dal lightly.
making paruppu rasam
In another pan, heat oil. Add the mustard seeds and urad dal.
Fry on low heat stirring often till the mustard seeds start crackling and the urad dal becomes golden.
Keeping the heat to a low add 10 to 12 curry leaves and 1 to 2 dry red chilies (broken and seeds removed). Fry for a few seconds stirring often until the curry leaves looks crisp and red chilies change color. Take care not to burn the spices.
Now add the turmeric powder and asafoetida. At this point you can switch off the heat if the pan has become too hot. Stir and add the roasted ground rasam powder.
Stir quickly and add the above tempered mixture to the dal or add the dal to this mixture. stir.
Add the tamarind pulp. Stir and mix well.
Simmer for 7 to 8 minutes or till you see a frothy layer on top on a low or medium heat. The raw aroma of the tamarind also has to go away.
Garnish the paruppu rasam with coriander leaves and serve hot, plain or with some steamed rice.
Notes
Use lentils that are fresh and not aged. Preferably use unpolished lentils.
You can vary the consistency but don't make it very thin as then the flavor will get diluted.
Use fresh spices and not rancid ones.
For a faint sweet taste, you can choose to add a bit of jaggery.
You can soak the lentils for 20 to 30 minutes prior to cooking them. Soaking lentils make them cook faster.