Cook the purple sweet potato noodles according to the packet instructions. Drain and set aside.
Bring the ramen stock and water to a gentle simmer in a saucepan. Add the broccoli, green beans and/or sugar snap peas and cook for a few minutes, until just tender but still slightly crisp. Add the edamame towards the end.
Add the vegetable gyoza to the simmering broth and cook according to the packet instructions, usually for a few minutes until heated through and tender.
Divide the cooked purple sweet potato noodles between two bowls. Ladle over the hot broth, vegetables and gyoza.
Sprinkle generously with sesame seeds and serve immediately.