1.Heat oil in wok; deep fry about 100g of the noodles, in batches, until crisp. Drain on absorbent paper.
2.Using same heated oil, deep-fry brown onion, in batches, until lightly browned and crisp. Drain on absorbent paper.
3.In a small bowl, combine fried noodles, fried onion, green onion and coriander leaves. Cool oil; remove from wok and reserve for another use.
4.In a large heatproof bowl, cover remaining noodles with boiling water; use fork to separate; drain.
5.In cleaned wok, cook paste, garlic and turmeric, add water and coconut milk; bring to the boil. Reduce heat; simmer, stirring, 2 minutes. Add chicken; cook, stirring, about 5 minutes or until chicken is cooked through. Add sauces, sugar and juice; cook, stirring, until sugar dissolves. Stir in chopped coriander.
6.Divide drained noodles among serving bowls; spoon chicken curry mixture into each bowl, then top with fried noodle mixture. Sprinkle chilli slices over each bowl.