Wash and halve the plantains. Put them in a pressure cooker with sufficient water and pressure cook for just one whistle (the plantains shouldn’t turn mushy) and turn off the gas. Once the pressure releases, transfer the plantains onto a plate with a slotted spoon. Remove the plantain skins, grate and keep aside.
Cut 1 medium onion finely. Chop the green chilli and coriander leaves. Grate the ginger and coconut.
Heat oil in a frying pan and temper with red chillies and curry leaves. Next add black gram dal, Bengal gram dal, mustard seeds and cumin seeds. Sauté for a couple of seconds.
Add grated ginger, green chilli and onions. Sauté for a couple of minutes. Add a dash of asafoetida and salt and combine well.
Add the cooked and grated plantains; toss gently on low heat for about 2-3 minutes till all the ingredients are mixed well. Sprinkle freshly grated coconut and combine well.
Remove and add a dash of lemon juice. Garnish with chopped coriander leaves.
Serve Chettinad Vazhakkai Podimas with white rice, rasam and papad.