Preheat the oven to 180°C conventional oven/ 160°C fan-forced (350° Fahrenheit/Gas 4).
Use a rolling pin to roll half of the puff pastry onto a sheet of non-stick baking paper (roll to a size that would fit in your baking tray). Transfer the baking paper to a baking tray. Roll the remaining puff pastry slightly larger than the first.
Arrange the mozzarella on the first pastry sheet, overlapping slightly and leaving a 1cm border around the edge. Add tablespoons of the Italian passata over the mozzarella. Arrange the ham on top of the mozzarella. Season with salt and pepper to taste.
Use a fork to lightly whisk the egg in a small bowl. Brush the outer edge with egg, then fold the second sheet of puff pastry over to enclose the filling. Press edges together to seal, then press down using the tines of a fork.
Brush the top of the sfoglia ripiena with beaten egg. Bake until puffed and golden (approximately 25-30 minutes). Cut into slices and serve immediately – buon appetito.
Note: Use the best quality ham for this recipe. Don’t be afraid to ask your local deli to try a small piece before choosing which ham to select – it will really pay off.