To prepare filling, heat 1 tbsp butter in a non stick pan, add 1 tbsp maida and fry till pink in color. Now take the pan out of the flame and add 1 cup milk, keep it stirring for no lumps. Now put the pan on high flame and let it boil (keep it stirring until a boil comes). When it starts boiling reduced the flame to low and add salt, chili flakes and crushed black pepper. Mix well.