Bring a pot of water to the boil and cook the noodles according to packet instructions. Drain and run under cold water for a couple of minutes. Place in a bowl and toss with the sesame oil.
In another bowl whisk together the peanut butter, rice vinegar, soy sauce, sesame seeds, honey, ginger, garlic, chilli flakes and sriracha. Stir in the grated cucumber, half the spring onion and half the peanuts.
Add the noodles to the sauce and toss thoroughly to coat. Split the noodles between serving bowls and top with sliced cucumber and spring onion.
Nutrition information is an estimate and will vary depending on the ingredients used.