Preheat the oven to 425°. In a large ovenproof skillet, cook the chorizo in the olive oil over high heat until lightly browned, about 4 minutes. Add the onion, garlic and fennel and cook, stirring, until the vegetables are crisp-tender, about 5 minutes. Add the rice and cook, stirring, for 2 minutes. Add the water, red pepper strips, olives and thyme, season with salt and pepper and bring to a boil. Cover and cook in the oven for 20 minutes, or until the rice is tender and the water is absorbed. Fluff the rice with a fork, discard the thyme sprigs and serve.