Braise beef (in big pieces) with ginger, galangal and water on low heat for 2.5 hours or until tender.
Cut potatoes into 2cm cubes and deep fry, set aside.
Make paste in food processor.
Once beef is tender, take out from the pot and set aside. Reserve beef stock in pot. Turn off the heat.
Optional: Once beef is cool and dry, heat up frying pan on high, add oil and sear the beef. This add smokiness to the beef.
Cut beef into 2cm cubes and set aside.
Heat up frying pan to medium, fry Paste and Aromatics in oil for approximately 10 minutes.
Mix in spices and cook for another 2-3 minutes, until fragrant. Turn off the heat, and transfer into the beef stock, cook the stock on low heat.
Stir in coconut milk, mix and cook for 15 minutes, stirring regularly until fragrant, season with salt and sugar.