01 - Heat olive oil in a large pot or Dutch oven over medium heat. Add the finely chopped onion and cook until softened, about 3 to 4 minutes. Add the minced garlic and sauté for 30 seconds until fragrant.
02 - Add the ground beef to the pot. Cook, breaking it apart with a wooden spoon, until evenly browned and no longer pink, about 6 to 7 minutes.
03 - Stir in the tomato paste, dried oregano, ground cinnamon if using, bay leaf, and a generous pinch of salt and pepper. Cook for 1 minute to allow the spices to bloom and release their aromas.
04 - Pour in the crushed tomatoes, broth, and water. Bring the mixture to a boil, then reduce the heat and let it simmer for 10 minutes so the flavors meld together.
05 - Stir in the orzo pasta. Cover the pot and simmer gently, stirring occasionally to prevent sticking, until the orzo is tender and most of the liquid has been absorbed, about 15 minutes. Add a splash of warm water if the mixture becomes too thick.
06 - Remove and discard the bay leaf. Taste the dish and adjust the seasoning with salt and pepper as needed. Serve hot, garnished with grated kefalotyri or parmesan cheese and a sprinkle of fresh chopped parsley.