Trim and Cut: Firstly, cut any stringy bits away from the livers, then cut them into strips. This helps ensure even cooking and tender results.
Brown the Livers: Then, heat a little olive oil in a heavy-based frying pan over high heat. Add the chicken livers and brown them by cooking for 2 minutes on each side. Remove from the pan and set aside.
Sauté the Onions: Next, lower the heat to medium, add a little more olive oil, and then add the chopped onions. Fry until softened, which should take about 5 minutes.
Add Spices: Then, add the sweet paprika, smoked paprika, and cayenne pepper to the onions. Fry gently for another couple of minutes to release their flavours.
Prepare the Sauce: Pour in the tomato passata and about 200ml of water. Stir to combine and bring to a gentle simmer.
Combine and Simmer: Return the browned chicken livers to the pan along with the sliced red peppers. Lower the heat to its lowest setting, stir well, and leave to simmer very gently for around 2 hours.
Monitor and Adjust: Check occasionally, adding more water if needed to keep the mixture from drying out. This slow cooking process ensures the livers remain tender and absorb the rich flavours of the sauce.
Season and Serve: Once cooked, season to taste with a little sea salt and black pepper. Serve hot, perhaps with a side of cauliflower rice or a fresh green salad.