Mix yogurt with chopped peppers and set aside for 10 minutes.
Heat oil in a large nonstick pan, add mustard and cumin seeds, once the seeds start to splutter add asafoetida and curry leaves.
Next add the peppers, salt and sprinkle some water. Cover and cook till pepper is tender, about 8~10 minutes.
Stir in poriyal powder and cook for another 2~3 minutes. Serve hot with rice.