1. Cook the spaghetti according to package directions. Reserve pasta water, then drain.
2. In a large sauté pan over medium-high heat, drizzle olive oil and cook the mushrooms until golden brown, about 2–3 minutes. Do not overcrowd the pan, or the mushrooms will not brown.
3. Add the sliced garlic and crushed red pepper, then cook for 30 seconds.
4. Add the cooked pasta and Yondu, then toss well. Add reserved pasta water if the pasta looks too dry.
5. Serve topped with chopped chives and chili flakes.