Peel and spiralize the sweet potato. Slice the onion, roughly chop the spring onion into half inch pieces. Slice the red pepper into thin strips. Julienne the carrot with a mandolin (or with a knife). Slice the mushrooms.
Heat a pan (preferably a wok pan or a large frying pan) until very hot.
Add a small drizzle of oil and fry the onion and spring onion for 1-2 minutes, until shiny and slighty softened. Add a small pinch of salt and set aside.
Fry the carrots for 1 minute, then add the red peppers and fry for 20 seconds. Add salt. Set aside.
Sauté the spinach until soft and wilted. Add salt, sesame oil and garlic. Set aside.
Fry the mushrooms until soft. Add salt. Set aside.
Add a little bit of oil in the pan. Add the sweet potato noodles to the pan and fry for 5 minutes or more, depending on how thick they are. You want them to soften, but don't fry too long so they don't get mushy. Add salt. Once cooked to your liking, set aside.