Step 1

To prepare the biga starter, mix all the biga ingredients together into very firm dough, by hand or in a standing mixer with a dough hook attachment. Place it in a bowl, cover with cling film and leave at room temperature overnight, for 15 – 20 hours. The biga will look like an overgrown cauliflower by the next day.

Step 2

Cut the biga into small pieces with a knife or scissors and place in the bowl of a standing mixer (or on a work surface if kneading by hand) with the flour, polenta, malt extract and water. If kneading by hand, add the water gradually to the mix. Knead or mix for at least 10 minutes until it comes together into a sticky mass. Add the salt and continue kneading or mixing at high speed for another 20 minutes until the dough is smooth and shiny.

Step 3

Place it in a large lightly oiled bowl and cover with cling film. Leave it for 30 minutes in a warm place.

Step 4

After that time stretch and fold the dough with oiled hands from all sides into the centre. Turn the dough over, with the stretched flaps down, and leave for another 30 minutes.

Step 5

Repeat stretching and folding and leave the dough, covered, for 10 minutes.

Step 6

Turn it out onto lightly floured surface. Shape it into a ball and place, seam side down, in a floured banneton or a bowl lined with a generously floured tea towel. Cover and leave to prove in a warm place for 30 minutes.

Step 7

Preheat the oven to 250C (fan if available)/475F/gas 9 with a pizza stone or a heavy baking tray on the middle rack.

Step 8

Taking care, turn the loaf out onto a peel or directly onto the stone or tray. Spray the oven with water and bake the bread for 25 minutes.

Step 9

Cool on a wire rack before slicing or cutting into wedges.