Tomato rasam / Indian soup

This rasam/soup is made of tomatoes and split pigeon pea. It is made in many South Indian homes and also served in restuarnts, weddings and feasts.     

Ingredients: 
Tomato - 1(cut into four pieces)
Tamarind pulp - 1/2 cup  
Cooked split pigeon pea -1/4 cup 
Turmeric powder -1 tsp
Rasam powder- 4 tsps
Asafoetida -1/4 tsp
Sugar - 2 tsps
Mustard seeds - 1 tsp
Chopped Coriander leaves -1 tsp
Salt and oil -as required

Method: 
Mash and mix the split pigeon pea in one cup of water. Keep it aside. Dilute the tamarind pulp with two cups of water. Cook the tomatoes in it along with asafoetida powder, turmeric powder, salt and sugar. When the tomatoes become mushy add the split pigeon pea liquid, rasam powder and more water. Check the consistency. Simmer for few seconds. Season it with mustard seeds fried in some oil. Garnish with coriander leaves.