In a stockpot over medium-high heat, heat the oil. Add the fennel, onions, and garlic and sauté them for about 5 minutes.
Add the tomatoes, oregano, 3 cups of water, and the brown sugar (optional). Raise the heat and bring it to a boil. Add the rice, reduce the heat to medium-low, cover, and simmer it, stirring occasionally, for 40 minutes.
Stir in the pepper and black beans and cook it for a few minutes more until it is heated through.
Serve it immediately, topped with plenty of Parmesan cheese, or refrigerate it for up to 3 days, or freeze it for up to 3 months