I made this with a couple of Sicilian friends when I was in Italy, and was astounded by the flavours from the potatoes – they marry so well with the rosemary and bread.
Put the flour, salt, yeast and water into a bowl and mix to form a dough.
Leave in the bowl to double in size for about 1 hour.
Line a baking tray.
Tip the dough out of the bowl onto the baking tray and flatten with your hands, then brush with olive oil and, using your fingers, make indentations over the surface.
Layer the potatoes over the top, sprinkle with a little rock salt and stud with the rosemary sprigs.
Leave to rise on the baking tray for 1 hour.
Preheat the oven to 230°C/450°F/gas mark 8.
Bake the bread for 30 minutes.
Remove from the oven and brush the loaf with more olive oil, then transfer to a wire rack and serve when cooled.