Firstly, wash mushrooms with cloth and remove stalk. Now dice in small pieces. Take 1-2 tbsp butter in a pan and place it on flame to melt. Add ginger in butter. After sauteing ginger add diced mushrooms, salt, black pepper and mix all ingredients really well. Cover and cook on low flame for 3-4 minutes and check later. After mushrooms turn juicy, cook for 2 more minutes as it is so that mushrooms turn tender.
Leave 1/4 part of mushrooms in pan and coarsely grind 3/4 part of mushrooms pieces in a mixture grinder. Place back the grounded mushrooms in pan with mushroom pieces and add 2 cup water. After it simmers once, dissolve 2-3 tbsp cornflour in water and mix in soup. Allow the soup to simmer for 2-3 minutes and add 1 tbsp cream. Turn off the flame and mix 2 tsp lemon juice into it.
Mouth drooling mushroom soup is ready. Take out soup in a bowl, garnish with cream and green coriander and serve steaming hot.
If you wish to add onion and garlic in soup, then add 1 finely onion and 4 garlic cloves (finely chopped) in butter and saute until onion turn pinkish in color. After sauteing onion add ginger, mushroom and follow the rest procedure for making soup.