Peel and cut a small piece of onion from stem side. Scoop out the inner portion. Boil it in salted water for 2-3 minutes.
Add all the masalas to moong daal and fill it in the onions.
Smear oil over onions. Cook in a hot oven for 10-15 minutes [or in a
karahi] until slightly brown. Decorate with tomatoes.