If you make sambhar powder and store it its easy to use that and make  sambhar whenever necessary. I usually fry the masala along coconut and grind it to make the sambhar and  wont add pepper or cumin seeds to the sambhar so my sambhar powder is also different.

Red chillies            : 200gms

Coriander seeds     : 100gms

Chana dal               : 3 tbsp

Fenugreek seeds    : 1 tsp

Asafoetida             : 1/2" pc

Oil                         : 1/2 tsp

Method:

Heat a fry pan, roast the chillies, coriander seeds, chana dal and fenugreek seeds one by one.  Remove from the pan and add oil to it. Then add the asafoetida and fry it.  Cool it and dry grind it to a powder.

Transfer it to a plate or paper to cool.  Store it in a container.