Prep the moong dal - wash and soak the moong dal in hot water for 15-20 minutes. Drain the dal after and use it in the poriyal.
Prep and chop - Wash the long beans and trim the edges. Chop the beans into small pieces.
If the long beans are tender, we can cook them directly in the pan. We can also steam them briefly in the Instant Pot to speed up the process.
To steam the long beans - Place the chopped beans in a steamer basket and then place them on a trivet inside the Instant Pot. Ensure the main steel pot has about an inch of water in the bottom. Set the Instant Pot in steam mode and set the timer for 2 minutes. Once the cooking process is complete, release the pressure in 5 minutes and remove the strainer from the pot.
Heat a wide pan and add the oil. Once the oil heats up, add the seasoning ingredients - mustard seeds followed by urad dal, red chilies, curry leaves, and then asafoetida.
Let the mustard seeds crackle. Once the urad dal is golden brown, add the steamed yard-long beans.
Add the soaked and drained moong dal as well and mix everything. Add salt and cook on low heat for about 5-7 minutes. Keep stirring the beans occasionally, so they don't stick to the pan.
Pro Tip - My mother always adds a little sugar in any stir fry/poriyal with coconut and this makes the curry more flavorful. If using sugar, add about 2 teaspoons of sugar now.
Add the grated coconut to the karamani poriyal and mix everything well. Cook for a minute and then take it off the heat.
Long beans curry is now ready to serve. Karamani curry is the best stir fry in a typical South Indian lunch menu.