Preheat the oven to 350°F. Grease a 3-quart baking dish with oil.

In a large skillet, heat the oil over medium heat. Add the onion, red bell pepper, and green bell pepper and cook, stirring occasionally, until softened, 3 to 5 minutes.

Add the ground beef and cook, breaking up the meat with a wooden spoon, until the beef is cooked through and browned, 6 to 8 minutes.

Add the tomato paste, salt, cumin, paprika, black pepper, and garlic; cook, stirring frequently, until fragrant.

Add the tomatoes and zucchini and cook until softened, 3 to 5 minutes.

Stir in the chicken broth, rice, parsley, Worcestershire sauce, and 1 cup of the cheese.

Remove from heat and spoon the mixture into the prepared baking dish and cover with aluminum foil.

Bake until the rice is tender and the liquid is absorbed, 50 minutes to 1 hour.

Remove the foil and stir the casserole. Sprinkle with the remaining 1 cup cheese.

Increase the oven to broil and broil until the cheese is melted and bubbly, 2 to 3 minutes.

Allow to cool 5 minutes before sprinkling with more parsley and serving.