Bring a medium saucepan of water to the boil for the noodles. Halve the carrot lengthwise and thinly slice on an angle. Cut the capsicum into strips. Coarsely chop the pak choy and peanuts.
Step 2 — Prep lime and chicken
Finely grate the zest of half the lime*, then juice the half. Thinly slice the chicken into strips.
Step 3 — Cook noodles
Cook the noodles in the pan of boiling water for 7 mins or until tender. Drain, then rinse under hot water to prevent the noodles from sticking.
Step 4 — Start stir-fry
Meanwhile, heat 2 tsp oil in a large deep frypan over high heat. Stir-fry the chicken for 2-3 mins until golden and cooked through. Remove from the pan. Heat 2 tsp oil in the pan. Stir-fry the carrot and capsicum for 2-3 mins until tender.
Step 5 — Finish stir-fry
Scrunch the lime leaves and add to the stir-fry (see cooking tip). Add the curry paste and cook, stirring, for 30 secs-1 min until fragrant. Add the pak choy, fish sauce, 60ml (¼ cup) water and 1 tsp sugar and cook, stirring, for 30 secs-1 min until the sauce is slightly reduced. Add the lime zest and 2 tsp lime juice and stir to combine.
Step 6 — Get ready to serve
Add the chicken and noodles to the vegetables and toss to combine. Divide the stir-fry among bowls. Scatter with the peanuts to serve.