Heat a pan over medium heat.
Fry the dried red chilies until they become fragrant and slightly darkened in color. Remove them from the pan and set aside.
Fry the Kashmiri red chilies until they become slightly fluffy and change color. Remove them from the pan and set aside.
In the same pan, fry the whole coriander seeds until they start to release their aroma. Remove them from the pan and set aside.
Combine the chana dal and urad dal in the pan and fry them together until the urad dal turns light brown in color. Remove them from the pan and set aside.
Add the fenugreek seeds and cumin seeds to the pan and fry them until they are roasted. Remove them from the pan and set aside.
Fry the parboiled rice in the pan until it becomes lightly golden. Remove it from the pan and set aside.
Over very low heat, fry the asafoetida until it releases its aroma. If you're using the asafoeitida powder then do not roast and use as it is.
Fry the curry leaves in the pan until they become crisp. Remove them from the pan and set aside.
Once all the ingredients have cooled down, grind them together into a fine powder using a spice grinder or blender.
Add the turmeric powder to the ground mixture and mix well.
Let the sambar powder cool completely before storing it in an airtight container.