Wash and cut all the vegetables listed in the ingredients list.
In a large pot, bring 3 liter of water to a boil over medium high heat. Add ½ tbsp of salt to the boiling water.
Reduce heat to medium low, add the spaghetti and cook it according to the package directions until al dente (my spaghetti took 10 minutes).
Optionally, cool down the spaghetti in iced water for a more al dente texture. Drain off the excess water.
Place the drained spaghetti into a large bowl, add all the seasonings listed under "Stir fry spaghetti sauce" over the spaghetti. Stir with a pair of tong until well mixed.
In a large frying pan, heat up 2 tbsps of cooking oil over medium high heat for 1 minute. Add in minced garlic, shredded carrot, and green onion pieces to stir fry for about 2 minutes until the carrots turn soft.
Add in celeries, cabbages, or any other vegetables of your choice (such as mushrooms, bean sprouts, or snow peas) to stir fry for about 2 minutes until they turn soft.
Pour the spaghetti with the sauce into the frying pan. Stir fry over medium high heat for 5 minutes, until all the sauce has been absorbed into the noodles. Tilt the pan to observe, there should be no sauce left on the bottom of the pan.
Transfer the stir fry spaghetti to two serving plates. Serve hot.