Cut the leeks into diagonal slices, julienne the carrot and red cabbages, cut the pepper into rings, the mushrooms - coarsely, and crush the garlic. In a deep pan (wok), heat the oil and fry the leeks and carrots for a minute.
Add the cabbage and mushrooms and fry them for 3-4 minutes on high heat, while stirring. Add the pepper and fry for another 2 minutes. Season the vegetable mixture with soya sauce and sesame oil and set it aside.
Boil the spaghetti according to package instructions, add spices and mix with the fried vegetables. Bring the dish to a boil and serve.