To make sweet potato noodles, use a mandoline and thinly slice sweet potato vertically. Cut the slices into thin strips. Alternatively, you can use a vegetable peeler to slice thin strips.
Heat oil over medium high heat. Add garlic, sweet potato noodles and a ¼ cup water to steam the noodles. Once water is evaporated, sauté for 3-4 minutes. Then, add the shiitake mushrooms and bok choy and continue to sauté.
Add ginger, soy sauce, hot sauce, and cook for 5-7 more minutes or until veggies have reached desired consistency.
Remove from heat, divide between two plates. Sprinkle with scallions and sesame seeds, if desired.