1.Heat oil in saucepan over medium-high heat. Add garlic, chilli, coriander stems and 2 teaspoon ginger and cook for 2 minutes until fragrant. Add stock water, star anise, palm sugar, soy sauce and 1 tablespoon fish sauce.
2.To make the meatballs; place chicken mince, 2 spring onions, handful of chopped coriander leaves, white pepper, remaining ginger and fish sauce into mixing bowl and stir well to combine (the best way to do this is with clean hands). Divide and roll mixture into 20 balls.
3.Increase heat to high, drop meatballs into stock and cook for 3 minutes until almost cooked. Add noodles and green vegetables, then cook for a further 2 minutes until noodles and vegetables are tender and meatballs are fully cooked.
4.Divide soup into 4 bowls and top with bean sprouts, mint leaves, remaining spring onions and coriander leaves.