For the noodles: Bring a pot of water to a boil. Cook the spaghetti in the boiling water according to the package instructions. Drain, then drizzle with some sesame oil and a little soy sauce in a large bowl and toss.
For the stir-fry: While the noodles are cooking, mix together the soy sauce, sherry, brown sugar, cornstarch, sriracha and ginger in a bowl. Set aside.
Heat the peanut oil in a large skillet over medium-high heat. Add the onion and bell peppers and cook, stirring, for 2 to 3 minutes. Add the garlic and cook for 30 seconds to 1 minute more, stirring continuously. Add the zucchini and stir it around, cooking it for 2 minutes more. Add the baby corn and broccoli and cook for a couple of minutes.
While the veggies are still firm, pour in the sauce. Stir the veggies in the sauce and cook until the sauce is very thick, 1 to 2 minutes more. If it needs to be a little saucier, pour in 1/4 to 1/2 cup hot water and splash in a little more soy sauce.
Serve the stir-fry over the noodles with a sprinkling of sesame seeds and some slice green onions.