Take the mushrooms into a bowl. Wash it properly.
Cut it into the two slices. Then deep it into the turmeric water for 15 minutes.
Now drain out the water from mushroom completely.
Put 1tsp mustard oil in a pan or kadai.
Add mushrooms , 1 tsp salt and mix it. Cook on medium flame till the water is dry from the mushrooms.
Now shift it into a bowl. In the same pan put 2tbsp mustard oil.
Add 1tsp mustard seeds, 1 tsp cumin seed, 1 green chili, and 8-9 curry leaves. Allow it to splutter.
After spluttering, add onion slices and 1 tbsp ginger garlic paste. Saute it on medium flame.
Then add chopped tomatoes, 1tsp salt, 1 tsp turmeric powder and 1tsp red chili powder. Mix it.
When the tomatoes are mushy, add fried mushrooms into it.
Then add 1tsp dhania/ coriander powder, garam masala powder. Mix it well.
Allow it to Cook for 1-2 minute on low flame by covering the mixture.
Now switch off the flame.
Serve it, by garnishing with coriander leaves.