Heat half the oil in a wok, or large frying pan, over a medium heat and fry the salmon, skin-side down, for 3-4 minutes. Turn over and cook for another 3-4 minutes. Transfer to a plate, then flake into large pieces, discarding the skin, and keep warm.
Meanwhile, bring a large pan of water to the boil, add the noodles and cook for 3-4 minutes. Drain, reserving 100ml cooking water.
Heat the remaining oil in the frying pan or wok and add the mixed pepper stir-fry, cooking for 2-3 minutes. Add the peas, most of the spring onions and the garlic. Stir-fry for 2 minutes more before pouring over the teriyaki sauce and the reserved cooking water.
Toss the noodles and salmon with the vegetables, drizzle over the soy sauce and serve garnished with the remaining spring onions and lime wedges.