Separate the stems from mushrooms. Keep aside. Make cavity in mushroom caps with knife. Keep aside. Finely chop the mushroom stems. Add chopped onions, garlic, green chillies, salt, black pepper, food colour and mix well.
Heat 2 tbsp of oil in a pan and add chopped onions, garlic, green chillies, salt, black pepper, food colour saute the above mixture for 2 minutes till it becomes dry. Add grated cheese to it after removing it from flame.
Take refined flour in bowl, add salt, food colour and prepare a thick batter. Keep aside. Now fill the mushroom caps with the mixture and hold two filled caps together with open ends facing each other. Bind them together by putting toothpicks into it.
Dip the mushroom into batter and roll it in breadcrumbs. Deep fry the mushrooms in preheated oil till it becomes golden brown. Serve as it is or remove the toothpicks and cut it into two pieces. Serve hot with tomato ketchup.