Clean and wash chicken bones and boneless chicken. Peel, wash and roughly chop onion and garlic. Soak tamarind in quarter cup warm water; remove the pulp, strain and reserve.
Wash and roughly chop the tomato and curry leaves. Boil the chicken bones in about seven to eight cups water, skim the scum from the surface and simmer for ten minutes.
Add roughly chopped onion, garlic, tamarind pulp, tomatoes, boneless chicken, salt, turmeric powder, red chilli powder, asafoetida and chopped curry leaves. Continue to simmer on medium heat for another fifteen minutes.
Remove cooked boneless chicken, cool and chop into bite sized pieces. Blend besan in quarter cup water and mix into the simmering soup. Add scraped coconut, cover and simmer for ten to twelve minutes.
Strain soup, pressing the residue well to extract the entire flavour. Reheat the soup, add chopped chicken, adjust the seasoning, mix in lemon juice and serve piping hot.