In a heavy bottomed pan, heat the coconut oil.
Add mustard and cumin seeds. Once seeds splutter, add asafoetida.
Give this a quick stir and add the sliced green beans. Stir on high flame for 30 seconds. Add the drained yellow mung, stir to combine for 30 seconds.
Reduce the flame. Add salt and combine with the beans and mung.
Make a well in the centre of the pan. Add 1/4 cup water.
Cover the pan and allow to steam cook for 6-7 minutes. Both the green beans and yellow mung should be cooked, but with a bite. Don't allow the mung to overcook and turn pasty.
Add the red chili powder, coriander powder, sambar powder and toss gently.
Cover and cook for 2 minutes on low flame.
Remove into a serving dish and garnish with fresh coconut.