
Add the flour to a large bowl. Add the chopped rosemary and a pinch of salt and stir to combine.
Add the water and whisk to a smooth, liquid batter.
Add ½ a tablespoon of olive oil to a medium-sized pan and heat it until hot on a medium heat. Pour ⅓ of the batter (a large ladleful) into the pan and quickly spread it out like you would a crepe in a spiralling motion.
Let the flatbread cook for about 2-3 minutes on each side until golden brown and the edges are crispy.
Remove to plate with kitchen paper and repeat with the next 2 flatbread adding another ½ tablespoon of olive oil each time for frying.
Cut the flatbread into slices just like a pizza and serve warm with cured meats and cheese. Traditionally, Pecorino cheese is grated over the top of the Brustengo and it's served with Prosciutto di Norcina.