Chop finely the snake gourd. Add van payar, turmeric and salt. Pressure cook for 2-3 whistles and remove from fire. Take the ingredients for grinding: grated coconut, cumin seeds and dry red chillies. Grind to a fine paste.
Open the pressure cooker and add the ground paste. Let it remain on low heat for a few seconds. Remove from fire before boiling starts.
Take a frying pan and pour oil. Refer the ingredients for seasoning. Splutter mustard seeds and add cummin seeds, curry leaves, red chilly, shallots and shredded coconut. Saute in low heat until the coconut turns golden in color.
Pour the seasoned mixture into the padavalanga mixture and stir gently.
Padavilanga/snake gourd erriserry is ready and serve hot.