Season the chicken: Generously season all sides of the chicken pieces with salt, pepper, oregano, and paprika.
Brown the chicken: Heat olive oil in a large oven-safe roasting pan or Dutch oven on the stovetop over medium-high heat. Brown the chicken for several minutes on each side until golden. Remove and set aside.
Cook the aromatics: In the same pan, add the chopped onions and garlic. Sauté until soft and fragrant.
Toast the orzo: Stir in the orzo and cook for a few minutes until slightly toasted.
Deglaze the pan with red wine: Pour in the red wine, scraping up any browned bits from the bottom of the pan, then add the tomato paste and mix it in well.
Add tomatoes and spices: Stir in the passata, ground cinnamon, allspice, bay leaves, oregano, and thyme. Add salt and pepper, adjusting to taste, and cook briefly to combine the flavours.
Add chicken stock: Pour in the chicken stock, ensuring the orzo is just covered. Gently mix to ensure even cooking.
Return the chicken to the pan: Nestle the browned chicken pieces back into the orzo mixture, skin-side up.
Bake: Transfer the pan to a preheated oven at 175°C (fan-forced) and bake until the chicken is fully cooked and the orzo has absorbed most of the liquid.
Rest and serve: Remove from the oven and let the baking dish rest. The sauce will thicken during this time. Give the orzo a gentle stir to mix everything together.