1Place stock, ginger, star anise, soy sauce and sugar in a saucepan. Bring to the boil over high heat. Reduce heat to low. Simmer, covered, for 15 minutes or until slightly reduced.
2Meanwhile, place fish, coriander, lime rind, and garlic in a food processor. Season with salt and pepper. Process until combined. Roll heaped tablespoons of mixture into balls.
3Place noodles in a bowl. Cover with boiling water. Stand for 5 to 7 minutes or until tender.
4Strain stock mixture into a bowl. Return to pan over medium heat. Add fish balls to stock mixture. Cook, stirring, for 8 to 10 minutes or until cooked through. Add snow peas. Cook for 1 minute or until tender.
5Divide noodles between bowls. Ladle soup, snow peas and fish balls over noodles. Top with coriander and serve.