Mix together the miso paste, rice vinegar, maple syrup and ½ tbsp sesame oil with 1 tbsp water in a bowl and whisk until smooth. Place the salmon fillets in a large bowl and pour the marinade over, making sure they are well covered with sauce. Cover with clingfilm and put in the fridge for at least an hour, and overnight if possible.
Heat a large non-stick frying pan over a medium heat and, when it's hot, add your salmon fillets. Cook for 7-8 minutes per side or until cooked in the middle. Meanwhile, cook the noodles according to the instructions on the packet.
Whisk together the almond butter, soy sauce and remaining sesame oil until smooth. When the noodles are cooked, drain, rinse briefly in cold water, shake off excess water and add to the almond butter mix. Toss until the noodles are well coated.
Peel the carrot and cucumber, then use a julienne veg peeler to make fine strips. Finely slice the spring onion. Sprinkle the vegetables on top of the noodles and mix to combine. Serve the noodles topped with the cooked salmon fillet and finish with a squeeze of lime juice.