This is one of the quick rasam recipes. If I come back late from work and dont have the energy to make any 'masala randayi', I make daali rasam with rice and some vegetable upkari. I do not use tomatoes for this rasam, but if you wish, you can add half a tomato. I made this at night and so the picture has a little glare.

What you will need:
1/2 cup toor dal(split yellow peas)
3 green chillies
a bunch of coriander leaves
tamarind - about the size of a lime ( soak in water and extract the juice)
or 1 tsp tamarind paste
4 tsp ghee/clarified butter
1 tsp mustard leaves
2 strands of curry leaves
salt to taste

2 tsp rasam powder
OR
Fry in oil and grind the following into powder:
1/2 tsp fenugreek seeds ( methi seeds)
1 tsp jeera ( cumin seeds)
12 peppercorns
1 tbsp coriander seeds
1/2 tsp turmeric powder
1/4 tsp hing (asafoetida)
1 tbsp toor dal
4 dried red chillies

How to prepare:
Wash and cook the toor dal along with green chillies in a pressure cooker.
Mash the toor dal well. Then add salt,tamarind juice/paste and chopped coriander leaves. Add the rasam powder and bring the dal to a boil. Keep aside. Heat ghee in a small pan and add mustard seeds. When the mustard seeds crackle, add the curry leaves and then pour it over the dal.
Serve hot with rice.