The dough for the bread mix is made the night before and left over night to prove so ready to get in the oven in the morning ready to be eaten warm for breakfast.
In a jug weigh the water, yeast, and honey and then stir well together to dissolve. Place the flour in a very large bowl, then add the yeast mixture and half the olive oil. Stir with a spatula until just incorporated, scraping the sides of the bowl clean and then cover with cling film. Leave out at room temperature for 12 to 14 hours until at least doubled in volume.
Spread the remaining oil evenly in approximately a 30 x 40 cm baking tray. When the dough is ready, rub a little olive oil on your hand and use to help release the dough from the sides of the bowl and fold it onto itself gently, then pour out onto the baking tray. Gently stretch the dough to the edge of the sheet by placing your hands underneath and pulling outward. The dough will shrink a bit, so repeat stretching once or twice.
Preheat the oven to 200C/fan 180C/gas 6. Dot the mixed berries all over the surface of the dough pressing them into the mixture to slightly submerge. Sprinkle with the pistachios and bake for 25 to 30 minutes until the bottom crust is crisp and golden brown and the top is golden and the berries have burst creating a lovely juicy topping. Let cool for 5 minutes, then release the bread from tin and transfer to a cooling rack to cool completely.
Serve warm or at room temperature.