Peel the chayote / chow chow and remove the seeds. Roughly chop it into small cubes.
Wash the dal thoroughly and soak it in water for 10 minutes.
Grate or chop the coconut and keep it aside.
In a small pressure cooker, preferably 2L pressure cooker, add chopped chow chow and chana dal.
Add turmeric powder, sambar powder and salt.
Pressure cook for 3 whistles with water on high flame. Let the pressure release naturally.
Meanwhile grind coconut, rice flour and cumin seeds together. First grind the coconut finely along with rice flour and then add the cumin seeds and grind coarsely to retain the aroma of cumin seeds.
Open the pressure cooker and check for doneness of the vegetable.
Now add the ground paste to the pressure cooker and mix well.
Heat oil in a pan and add mustard seeds. Once the mustard seeds seeds crackle add urad dal and chana dal.
Once the dals are browned, add curry leaves and green chilli. Add a pinch of asafoetida.
Pour the tadka mixture into the pressure cooker and allow it to boil for around 5 minutes on low flame.
Garnish with coriander leaves and serve hot.