Chop carrot, potato, onion, tomato into small pieces. Add these to pressure cooker
Now add the mutton bones, garlic, ginger, coriander powder, black pepper, cinnamon stick, 6 cups of water, salt as needed into the pressure cooker and cook for 5 to 6 whistle. Once the pressure is released; mash the vegetables and keep the soup aside.
-- Preparation of dumpling --
Chop liver, onion, mint leaves, coriander leaves, green chili into small pieces.
Squeeze all the milk from the soaked bread slices.
To the bread slices add liver, onion, mint leaves, coriander leaves, green chili, egg, lemon zest, black pepper powder, maida flour as needed and make a dough like you do for vadai.
Now make small balls out of the dough.
Place the cooked soup in a low heat and bring to boil. Now add the liver balls into the boiling soup and cook for 20 minutes. Remove from heat and keep it aside.
When you server the soup melt the butter and pour into the soup then serve.