Bring a large pot of water to a boil. Once boiling, add the noodles and cook until just tender, about 6 minutes. Drain the noodles and rinse with cold water to stop them from cooking any further. Set aside.
In a medium bowl, mix together the nutty peanut butter, fish sauce, soy sauce, rice vinegar, light brown sugar, and Sriracha hot sauce until everything is blended together into a smooth sauce.
In a large skillet over medium-high heat, sauté the garlic and green onions for 2 minutes or until aromatic. Then add the bean sprouts and peppers to the pan and cook for another minute.
Add the noodles and peanut sauce mixture to the pan, stirring until everything is combined. Cook for an additional 5 minutes while stirring occasionally.
To serve, garnish with chopped cilantro and salted peanuts. Enjoy warm with a few lime slices on the side!