To prepare avarakkai poriyal, wash the beans well and dry using a kitchen towel. Top and tail the beans and remove any strings along the sides. Tender beans wont have the fibrous strings, so can be used just after slicing off the top and tail.
Stack up 10-12 beans together and finely slice them.
In a pressure cooker, place the sliced beans along with 1/4 tsp salt and 1/4 cup water. Pressure cook for 1 whistle. Switch off the flame. Once cooled, remove from the cooker and drain out the cooked beans. Any excess water drained out from the beans can be used in rasam. Allow this to sit in a colander, while you prepare the tempering.
In a heavy bottomed kadai, heat the oil.
Add the asafoetida, udad dal, mustard seeds. Once the udad dal turns golden and mustard seeds splutter, add the curry leaves and dried chillies.
Stir this for few seconds, and add the drained cooked beans.
Add 1/4 tsp salt and toss everything together.
Garnish with fresh coconut and serve hot with rasam and rice.