Chop onion length wise.
Chop Brinjal/vankaya also length wise and put them in water to avoid decolouring.
Slit green chillis.
Heat oil in a kadai.
Add urad dal and chana dal.
Add mustard seeds and cumin seeds.
Allow them to splutter.
Add slit green chillis and red chillis.
Saute them for a minute.
Add sliced onion.
Fry them till they turn translucent.
Add sliced vankaya/brinjla.
Combine them well. Add turmeric powder and salt.
Mix them well. Add water and cover.
Cook for 5 minutes.
While stirring occasionally cook till the vankaya become soft.
Add milk and cover.
Cook for another 10 minutes on a low flame.
Keep stirring occasionally.
Let the vankaya absorbs all the milk and moisture.
Switch off the flame and transfer the curry into serving bowl.
Serve vankaya paalu curry with rice or roti.