Cook the noodles according to packaging instructions. 

Meanwhile, stir together the garlic, tamari, rice vinegar, sesame oil if using, hot sauce, water and cornstarch. 

When the noodles are done, drain and rinse and transfer to a non-stick frying pan together with the sauce. 

Toss together until the noodles are coated and the sauce is thickened. Serve with sesame seeds, green onions and chilli flakes.