Preheat oven to 200ºC (390ºF). Place the capsicum, chorizo and olive oil on a baking tray and toss to combine. Roast for 25–30 minutes or until the capsicum is tender and the chorizo has browned. Cook the spaghetti in a saucepan of boiling, salted water for 10–12 minutes or until al dente. Drain and return to the pan. Add the roasted capsiucm, chorizo, basil and lemon zest and toss to combine. Top with parmesan to serve.