Dissolve the vegetable stock cubes in boiling hot water. Add the soy sauce, balsamic vinegar, ketchup, sesame oil and spices. I always make the quantities by feeling, the information is for guidance only. I also use very sweet ketchup - if you don`t have it, you can add a pinch of sugar. Season the finished sauce to taste. I always dip a vegetable stick in the sauce. It has to taste very spicy.
Heat a good portion of olive oil in the wok and swirl it with it. Let cool down. Then heat again and add the prepared vegetables. Fry for 5 minutes over high heat and constantly turning.
Then add the sauce and wok noodles and stir-fry for another 5 minutes over medium heat.