In a pot, boil water for the pasta and add salt and a little bit of olive oil so that the noodles don’t stick to each other and form clumps. Add in the noodles and cook it until al dente (8-10 mins).
TIP: Keep a cup of pasta water for later before draining the noodles.
In a small mixing bowl, mix together soy sauce, mirin, brown sugar, rice vinegar, minced garlic, and grated ginger to make the teriyaki sauce.
Now in another bowl, add the cornstarch powder to ¼ cup water and mix until the cornstarch slurry is formed.
Heat some oil in a saucepan, or a wok if you have one and add the teriyaki sauce over medium heat. Bring it to a simmer and then slowly pour in the cornstarch slurry while continuously stirring. This is to thicken the sauce. Cooke for 2 more minutes and then cut the heat.
Add the cooked noodles to the sauce and mix gently until combined.
Serve hot and top with optional sliced green onions, sesame seeds or sesame oil.