In a mixture jar, add ginger pieces and green garlic. Add some water and grind it into a smooth paste. Keep it aside.
Now in a mixture jar, add onion pieces and grind them into smooth paste. Keep it aside.
Then add tomato pieces and grind them into puree. Keep it aside.
Now in a pan, heat oil. add onion paste and saute it.
Then add ginger-garlic paste and saute it.
Now add tomato puree and salt. Cover and cook gravy till oil separates from its sides.
Then add turmeric powder, red chilli powder, coriander powder, garam masala, and sev usal masala. Saute it.
Now add 3 cup water, mix well and bring it to a boil.
When the gravy starts boiling, add boiled green peas and mix well.
Now in a bowl, add besan and some water. Mix well and add the mixture into gravy.
Then lower the flame and boil usal on low flame for 7-10 minutes.
Usal is properly cooked and the gravy become slightly thick.
Switch off the gas and add lemon juice and coriander leaves. Mix well.
Usal is ready to serve.