1On another wok, add 2 tablespoons of flour to 1 tablespoon of oil.
2Fry until golden and leave flour mixture aside to rest.
3 On a non-stick wok, heat 1 tablespoon of cooking oil.
4Fry onion, star anise, cinnamon bark, garlic and ginger for around 1 min till fragrant.
5Add marinated oxtail into wok, fry until slightly golden brown.
6Add water to wok till it barely covers the oxtail and let it boil.
7After the water boils, add the contents into a slow cooker and let it cook for an hour.
8Add carrots and let it cook for another 30 mins before adding potatoes and letting it simmer.
9Stir in flour mixture until desired consistency and add beef cubes to taste.