Prepare the Chicken: Pat the chicken breasts dry with a paper towel. This is crucial for getting a good sear. Season them generously on all sides with salt and freshly ground black pepper.

Sear the Chicken: Heat the olive oil in a large, oven-safe frying pan or skillet over a medium-high heat. Once the oil is shimmering, carefully place the chicken breasts in the pan. Sear for 4-5 minutes on each side, until they are deeply golden brown. Don't move them around too much. Once seared, remove the chicken from the pan and set it aside on a plate.

Sauté the Aromatics: Reduce the heat to medium. Add the sliced red onion to the same pan and cook for 5-7 minutes, stirring occasionally, until it has softened and is starting to sweeten. Add the sliced garlic, dried oregano, and fresh rosemary and cook for another minute until fragrant.

Deglaze the Pan: Pour in the white wine to deglaze the pan. Use a wooden spoon to scrape up any browned bits stuck to the bottom – this is where so much flavour is hiding! Let the wine bubble and reduce by about half, which should take 2-3 minutes.

Build the Sauce: Add the halved cherry tomatoes, the tin of whole plum tomatoes (crushing them with your spoon), and the tomato purée to the pan. Stir everything together. Season with a pinch of salt, pepper, and the optional sugar. Bring the sauce to a gentle simmer.

Combine and Bake: Preheat your oven to 180°C (160°C fan). Nestle the seared chicken breasts back into the sauce in the pan. Spoon a little of the sauce over the top of each piece of chicken.

Roast to Perfection: Transfer the entire pan to the preheated oven and bake, uncovered, for 15-20 minutes, or until the chicken is cooked through and the sauce is bubbling and slightly thickened. The internal temperature of the chicken should read 74°C on a meat thermometer.

Rest and Garnish: Carefully remove the pan from the oven. Let the chicken rest in the sauce for at least 5 minutes before serving. I find this final rest makes the chicken even more tender. Garnish generously with fresh basil or parsley leaves before taking it to the table.