Heat the butter and oil in a large pan or skillet over medium-high heat.
Add the mushrooms, mix gently such that butter coats mushrooms.
Now cook for about 4-5 minutes , when mushrooms starts to release water , move mushrooms to one corner and make some space.
Now add some butter, chopped onion and minced garlic. Sauté the onion until softened.
Mix well everything and saute until mushrooms turns golden and crispy on the edges.Take care not to burn garlic .
Add soya sauce and white vinegar , saute for a minute.
Season with salt and pepper as per your taste.
Stir through 2 tablespoon of cilantro.
Sprinkle any herbs( thyme , basil , parsley ) of your choice for extra kick of final flavour and serve warm.