First soak the mushrooms and basmati rice in separate pans for half an hour. Drain and keep aside.
Cut the mushrooms into small pieces. Heat oil in a pot (handi). Add the whole spices and sauté till they start crackling. Add the onions and stir-fr till golden brown in colour.
Add the ginger garlic paste dissolved in a little water and sauté further.
Stir in the vegetable stock and bring to a boil. Add salt, butter and juice of half a lemon. Now add the rice and cook on medium heat, stirring occasionally. When the water is reduced to the level of the rice, sprinkle milk on top and cover with a wet cloth. Cook on very low heat for 15 minutes or until the rice is cooked.
Heat the remaining butter in a pan and sauté the black mushrooms for a few minutes. Remove and keep aside.
Remove the prepared rice to a serving dish and serve hot, garnished with fried mushrooms.
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