Heat oil in a pan and add mustard seeds along with curry leaves, green chilly, garlic cloves, ginger garlic paste and saute for some time...
Then add chopped onion and saute.
Add chopped tomato and again saute for some more time.
Now add turmeric powder, pepper powder, garam masala, chilly powder along with required salt and mix well.
Add 1 cup water, mix well and let it boil.
Then add the boiled green gram into it, mix well and cook for 5 to 10 mins.
Green gram masala curry is ready. Transfer it to a serving bowl and serve hot.