Wash and cook Arbi in a pan till done. Arbi can be cooked in a pan of water or the microwave. Once cooled, peel skin and chop into rounds of 1" thickness.
Chop drumstick into small pieces. Microwave for 5 -7 mins in microwave. Prep the snake gourd and wash well. Chop into small pieces. Snake gourd can be cooked in the gravy itself. Keep all the vegetables aside.
Pressure cook toor dal till done with turmeric and few drops of oil. Keep it aside.
Heat a pan with oil, add mustard, urad dal, curry leaves. When the mustard pops add the finely chopped onions. Saute till the onions turn colour. Add green chilies, red chilies. Saute for a couple of minutes.
Then add finely chopped tomatoes. Add salt, turmeric powder, simmer till the tomatoes turn soft. Then add the vegetables, saute in oil for a couple of minutes.
Next add the red chili powder, followed by the tamarind pulp. Add 1 cup water and bring to boil. When it starts boiling, simmer and cook with lid covered for 15 mins.
Serve with steaming rice and potato chips