Wash the raw banana under running water and peel the skin. Cut off the ends and discard.
Rinse the banana well. Slice them to equal sizes. Do not slice them too thick or too thin.
Keep them in water until used to prevent browning.
Heat a wide pan with oil.
Add mustard, cumin, red chili and urad dal.
When the dal turns slightly golden, add the curry leaves and hing.
Lower the flame completely and wait until the leaves turn crisp.
Then add in chili powder, turmeric and sambar powder.
Mix them well in oil.
Quickly drain and add in the sliced banana pieces.
Mix well and fry tossing for two minutes.
Sprinkle 1 to 2 tbsp of water and mix well.
Cover and cook on a low to medium heat. Keep stirring them in between.
Check if the pieces are cooked. If needed add 2 tbsp more water and mix. Continue to cook until the pieces turn tender.
Sprinkle salt evenly.
Sprinkle 1 tbsp of water again for the salt to dissolve and coat the pieces well.
Cover and cook on a very low flame for 2 mins. If you prefer them crisp then avoid water and keep frying.
Serve vazhakkai fry with rice, sambar or rasam.