Pick the leaves from the curry patta sprigs. Wash the leaves well with water. Spread them on a kitchen cloth for a few hours to get rid of any excess water.
Heat oil. Add asafoetida, cumin seeds, mustard seeds, and fenugreek seeds and let them crackle for 3-4 seconds.
Add chana dal, urad dal, Kashmiri dry red chilies, and whole coriander seeds to the pan and fry on low heat until they turn slightly brown. Stir continuously to avoid burning.
Now add the washed and dried kari leaves and dry roast on low flame until they turn crisp. It will take 15-20 minutes. Stir very frequently.
Add a lime size ball of seedless tamarind, grated fresh coconut, and salt and fry for another 2-3 minutes. Stir frequently.
Remove the pan from heat and let the roasted ingredients cool completely. Transfer the cooled ingredients to a grinder or a food processor and grind to make a coarse powder.
Store the powder in an air tight container in the refrigerator for up to a month.