In a large pot of boiling salted water, cook the orecchiette until just al dente. Drain the orecchiette. Meanwhile, in a large, deep skillet, heat the olive oil until shimmering. Add the onion and cook over moderately low heat until softened, about 5 minutes. Add the asparagus and crushed red pepper and cook over moderate heat until crisp-tender, about 3-4 minutes. Add the pasta and the broth to the skillet along with the lemon juice and zest; season with freshly ground pepper. Cook, stirring, until the pasta and the asparagus are just tender, about 2 minutes. Add the goat cheese and stir until melted. Transfer the pasta to bowls and serve with Parmesan cheese. 2 large, or 4 small servings.