Mix diced onion and sherry vinegar together in small bowl and let stand for at least 15 minutes to lightly pickle the onions.
Bring large pot of salted water to a boil. Cook pasta until tender but still firm, about 6-7 minutes. Drain pasta well and allow it to cool to room temperature. Once cool, drizzle with olive oil and toss to coat.
While pasta is boiling, cook chorizo in small skillet over medium-high heat until chorizo is crisp. During last minute of cooking, stir in garlic.
In a large mixing bowl, toss together the pasta with chorizo and garlic mixture olive oil, parsley, green onions, piquillo peppers, Manchego cheese, thyme, smoked paprika and lemon zest. Add vinegar and onions to the salad. Toss well and season with sea salt and ground black pepper to taste. Drizzle with olive oil, to taste.
Serve immediately at room temperature or assemble one day in advance and refrigerate. Return to room temperature and toss well before serving.