Place noodles in a large heatproof bowl. Cover with boiling water and stand for 10 minutes or until just tender. Using a fork, separate noodles, then drain well.
Meanwhile, place lime juice, fish sauce and sugar in a bowl, stirring until sugar has dissolved
Place half the oil in a wok over medium-high heat, swirling wok to coat. Stir-fry chicken, in 2 batches, for 3 minutes or until browned. Transfer to bowl with sauce. Add remaining oil to wok, then add onion, garlic and chilli and stir-fry for 30 seconds or until fragrant. Add carrot and beans and stir-fry for 3 minutes or until just tender. Make a well in the centre of vegetables, then add egg and cook, stirring occasionally, for 30 seconds or until set. Roughly break into pieces.
Add noodles, chicken and sauce to wok and stir-fry for 2 minutes or until heated through. Add coriander, tossing to combine. Divide among bowls, then scatter over peanuts, and extra coriander and chilli. Serve with extra lime wedges.