Make the dipping sauce by placing the ingredients in a small pot and boil on medium heat for 5 minutes. If making this the night before, place in an airtight container and let cool in the fridge. If making this the day-of, make an ice bath and place the container of sauce into ice bath to cool faster.
Boil the buckwheat noodles according to package. When done, rinse under cold water and drain well so the noodles don't become soggy.
Portion out noodles and then the dipping sauce into a separate bowl. Add chopped scallions and toasted white sesame seeds to the sauce. Separately, you can also add 1 teaspoon of sesame oil to your noodles to add even more depth in flavor.You can also add all the ingredients over the noodles and mix to enjoy!