Start with the sauce. Peel the shallot and chop finely, sweat in a pan with a drizzle of extra virgin olive oil on a low heat, stirring often so as not to burn it. Add the tomato passata, season with salt and pour in a ladle of water. Cover and cook over low heat for 20 minutes. Meanwhile, cut the chicken breast into strips about 1/2 inch thick and then into irregular pieces of about 2 inches in length. Pass the chicken strips in the flour and, gradually, arrange them on a tray lined with greaseproof paper. Heat a frying pan with oil and then sear the chicken strips, cooking over high heat for 2-3 minutes, stirring occasionally. When they are golden, add salt and finally add the tomato sauce. Cook at a high heat for another 2 minutes and then turn off the heat.
Add the diced mozzarella and tear the basil leaves by hand, season with black pepper and mix together. Pour into a baking dish, sprinkling the top with grated Parmesan. Bake, in a preheated oven at 450-475°F in grill function, for 8-10 minutes or until the mozzarella has melted and the top is golden. Your Sorrentina chicken strips are ready to be served.