Shred the cabbage, chop the potatoes, mince the garlic and ginger and set aside.
Heat butter on medium heat.
Add the garlic, ginger, onion and saute till aromatic.
Add the potato and saute for a minute.
Add the shredded cabbages and saute for another minute.
Add the water, salt and black pepper and let the mix come to a boil.
Cover and simmer for another 7 minutes so that the potatoes are cooked.
Stir in half a can of coconut milk for a thin soup. If you want it creamier, add more of coconut milk.
Simmer for another 3 to 4 minutes.
Add the finely chopped Indian borage leaves or any herb you like and remove from heat.
Serve the soup warm.