Wash fresh curry leaves thoroughly and dry completely. Add 1 tsp oil in a wok and place curry leaves into it. Saute for while until they get crunchy. Take out roasted curry leaves in a plate.
Add rest of the 1 tsp oil in the wok and add chana dal first. Saute until it turns slightly brown in color. Now add red mustard seeds, cumin seeds, fenugreek seeds, black pepper and saute all until they turn brown in color. Turn off the flame and allow the spices to cool.
Add red chilly powder, mango powder, asafoetida powder and salt to the roasted spices and place them in mixture grinder. Ground to make coarse powder. Curry powder is ready.
Store curry powder in an air tight container for up to 2 to 3 months. Use in making rice, idli, dosa, uttapam, curd, raita and relish eating.