Heat a large pot on a medium-high heat and dry fry the star anise and cinnamon stick until fragrant. Remove from the pot and set aside.
Pour a splash of olive oil to the pot and working in batches, add a few shin pieces at a time and fry until browned on both sides.
Add the chicken stock, soy sauce, fish sauce, chillies, ginger, sugar, kaffir leaves and toasted star anise and cinnamon stick to the pot and bring to the boil.
Reduce heat to low, cover and simmer for 2 hours.
Remove the lid and use a spoon to skim off any fat that has risen to the surface.
Stir in the aubergines and cook uncovered for another hour until the beef is falling off the bone.
Garnish the hotpot with fresh coriander and chillies and serve with steamed rice.