For the vegetable spaghetti, clean and peel the carrots, wash, dry and clean the zucchini. Slice both lengthwise into thin strips with a peeler or on a vegetable slicer and cut into julienne.
Quarter the bell bell pepper, remove seeds, peel and cut into julienne. Clean the leek, cut in half lengthwise, wash, separate the individual leaves and also cut into julienne. Finely chop the garlic. Finely dice the onion. Peel the tomatoes, remove the seeds and cut into small cubes.
Heat olive oil in a pan. Sauté the leeks and a little later the carrot, bell pepper and zucchini strips over medium heat for a few minutes, stirring. Mix in the garlic, season with salt and pepper and remove the vegetables from the pan. Add a little olive oil if necessary and sauté the onion until translucent.
Mix in honey, let it caramelize a bit and add the diced tomatoes. Sauté, deglaze with soy sauce and balsamic vinegar, season and slowly stew until soft. Finally, mix with the vegetables. Cook spaghetti in plenty of boiling salted water until al dente, drain in a colander, drain well and add to the pan. Mix the spaghetti with the vegetables and season to taste. Serve the vegetable spaghetti immediately.