Heat oil in a medium skillet over medium-high heat. When shimmering hot, add mustard seeds and allow them to pop. Then add asafetida, urad dal, curry leaves & red chilies. Cook, stirring frequently, until fragrant and dal turns light golden brown, about a minute.
Add green beans, salt; cover and cook, stirring occasionally until beans are crisp-tender, about 3 to 5 minutes. Stir in coconut.
To make the optional garnish of fresh spice mixture - Roast Chana dal, then add coriander seeds and dry roast on the stovetop in a small pan. Coarse grind along with the red chili. Sprinkle over Green Bean Poriyal for a nutty and spicy flavor boost!
Equal amount of roasted peanuts or chana dal can be substituted for Urad Daal
You can also use frozen green beans instead of fresh in this recipe. Simply stir fry a few minutes longer.