For the sauce: 2 tablespoons reduced sodium soy sauce, or more, to taste
2 teaspoons sugar
1 teaspoon sesame oil
1/2 teaspoon ground ginger
1/2 teaspoon Sriracha, or more, to taste
In a small bowl, whisk together soy sauce, sugar, sesame oil, ginger and Sriracha; set aside.
In a large pot of boiling water, cook noodles according to package instructions; drain well.
Heat olive oil in a large skillet or wok over medium high heat. Add garlic, mushrooms, bell pepper and carrot. Cook, stirring frequently, until tender, about 3-4 minutes. Stir in snow peas and spinach until the spinach has wilted, about 2-3 minutes.
Stir in egg noodles and soy sauce mixture, and gently toss to combine.