Whisk together the peanut butter, white miso, rice vinegar, soy sauce, sugar and MSG until smooth
Slowly drizzle in the water while whisking until the sauce is velvety and pourable, then set aside
Slice the cucumber into thin half moons, pick the coriander leaves and finely slice the green tops of the spring onions
Combine the cucumber, coriander and spring onion tops in a bowl and chill in iced water if desired
Add the garlic, gochujang, Korean chilli flakes, dark soy, rice vinegar, sugar and white parts of the spring onions to a blender and blitz until smooth
Heat a large frying pan over high heat and add the oil
Add the chicken mince, press it flat and let it brown deeply on one side before breaking it up
Cook the chicken through, then pour in the chilli sauce and stir
Let the mixture bubble for 2-3 minutes until thick, sticky and fully coating the chicken
Cook the noodles according to pack instructions and drain
Toss the noodles immediately with the miso peanut sauce and a splash of warm noodle water until glossy and well coated
Divide the saucy noodles between bowls and top with the spicy chicken and herb salad
Finish with extra miso peanut sauce if desired
