Pasta: In a large pot bring water to a boil. Cook noodles per package directions, drain, and set aside.
In a wok or large pan over medium-high heat, add peanut or grapeseed oil and let heat until glistening. Add diced chicken and salt. Let cook for 2 minutes, then stir. Cook for 2 minutes more or until browned and cooked through. Remove chicken from pan.
Add broccoli florets to the hot pan. Let cook 1-2 minutes. Add garlic and ginger, then pour in tamari and stir until mostly evaporated. Add chicken back to the pan, stir, and remove from heat.
Sauce: In a small sauce pan over medium-low heat, add the peanut butter and 1/4 cup of the hot water, stirring to combine.
Mix in the rest of the ingredients, then add the remaining 1/4 cup water to thin the sauce to desired consistency.
Toss noodles, chicken and broccoli in the sauce. Serve with Sriracha and peanuts if desired.