Method:
Devein shelled shrimp & grind to a fnie paste. mix with cornflour, salt and green chillies
Make small marble-sized balls, fry in hot oil and keep aside
Cut turnip and capsicum into 1" cubes. Deseed tomatoes & cut into 1" cubes.
Parboil the turnips and drain
Melt butter and chopped & whole onions fry till pink, add capsicum, mushroom & fry for 5 minutes
Add turnip, tomatoes, garlic and ginger paste, stir fry gently till tomatoes are soft 
Add red chilli powder & fry for 2 minutes
Add milk & 1/2 cup water
Add shrimp balls, allow to boil till the gravy thickens
Mix coriander leaves & serve hot.

Note: Don't over fry to maintain the natural colours of capsicum & tomatoes.