Wash and clean Kantola and trim top pointy part, then slice each kantola length wise into 4 pieces. Chop onion into thin slices and keep aside.
Heat the oil in kadhai. Once heat enough, add cumin and mustard seeds. Once start crakling, add pinch of hing, then add garlic and stir it till golden.
Now add sliced onion and stir it for a mins, then add sliced kantola and mix it.
Add turmeric, red chili powder, coriander powder, salt, stir it, cover it and cook for 10-15 mins on medium flame. Check in between and stir it.
Once cooked, add amchoor powder, sugar and stir it again for a minute and switch of the flame.
Kantola Nu Shaak is ready, serve with rotli, dal bhaat or Thepla.