As we know that readymade sambar powder is available easily at market, but homemade sambar powder is of lesser price and also have more flavor. Do fry all the ingredients on low heat gradually.
If you are using asafetida grain instead of asafoetida powder than soak them in some water before use. Use only 1-2 grains
To make a good Rasam, never stir the tomatoes in the mixi to extract the juice. Rasam made of thick tomato puree becomes thick. Simply strain the boiled tomatoes and strain them through a sieve to remove the juice.
Adding a teaspoon of desi ghee to hot sambar and rasam, it enhances the taste and aroma while serving.
Always remember Dosa is made from sela rice and therefore do not replace with normal rice.
For making dosa, Dal should be very finely ground, until it is light and slightly sticky to the touch. It takes some time, so do it with patience.
If curry leaves are not easily found, then you can keep them in a polythene bag with stalks in the refrigerator for a month, it will dry up but the taste and aroma will remain intact.