Prep: 1. Bring 2 quarts of water to boil in large pot. 2. Cut broccoli into florets. 3. Slice mushrooms. Cut onion into wedges. 4. Mince garlic and grate ginger. Make: 1. In boiling water, cook broccoli until crisp-tender, about 2 minutes. Transfer to a plate with a slotted spoon. 2. Add spaghetti to boiling water, cook according to package instructions; drain and set aside. 3. Meanwhile, prepare the sauce - mix broth, soy sauce, rice vinegar, toasted sesame oil, hot red pepper flakes, and sugar. Set aside. 4. Heat a skillet over high heat. Add 1 tablespoon of oil and the onion; stir-fry until crisp and spotted brown, about 1 minute. 5. Add mushrooms and broccoli; stir-fry until just cooked, about 2 minutes. 6. Add garlic and ginger; stir-fry until fragrant, about 30 seconds. Transfer everything to a plate. 7. Add remaining 1 tablespoon of oil to the empty skillet; heat until shimmering. Add spaghetti; stir-fry until heated through, about 2 minutes. 8. Return vegetable mixture to pan, along with sauce; stir-fry to combine. Serve immediately.
If you want to add a little protein you can easily add tofu or chicken to this. Add cubed chicken to the hot skillet with the onion. Sliced tofu can be added after the mushrooms. This is also a great way to use up any leftover meat in the fridge. If you like a lot of sauce you'll want to make a little extra if adding meat.