In a small bowl, whisk together soy sauce, sugar, sesame oil, ginger and Sriracha. Set aside.
Set a medium pot of water to boil. Add lo mein egg noodles (or spaghetti) and cook according to package directions. Drain well.
In a large skillet, heat olive oil over medium-high heat. Add garlic, mushrooms, bell pepper and carrot. Cook until tender, stirring frequently, about 5 minutes. Stir in snow peas and spinach. Cook until spinach has wilted, about 2 minutes. Stir in noodles and soy sauce mixture, gently tossing to combine. Serve immediately.