Heat oil over medium-low heat in a pot. Add in garlic, ginger and chilli and fry, stirring continuously, until you can smell the fragrance, a couple of minutes. Don't let the mixture burns! If it burns, start over.
Add in the tau cheo and sugar and fry for a few more minutes then add in the pork, browning the sides a little. Add in water until 3/4 up the pork and bring to a boil. Add in dark soy sauce. Cover and simmer for 30 to 45 minutes until the meat is tender.
Taste the sauce and if it's too salty, add more sugar. Slice the pork into thick chunks and transfer onto a serving plate. Scoop the sauce on top, garnish with chopped spring onions and serve.