From our friend Egoitz Fernandez, a favorite of his Arto Opila (corn/wheat bread). 

Corn Soaker

The night before:

Mix together the corn and water (Water at 90 degrees Celsius) until there is no dry flour lumps, let it cool down and cover.

Baking day:(desired dough temperature 24 degrees Celsius)

Add the mix of corn and water from day before
yeast (optional). (we do not use it in bakery but feel free to experiment)

Mix everything except salt and yeast if using and let it covered for a 25 minute autolyse.

After autolyse, mix everything together, if using a mixer do not mis further than 6 minutes.

Let it ferment at room temperature for 35 minutes and the put the dough covered in the fridge for about 20 hours.

the next day (baking day) let the dough about 30 minutes at room temperature before dividing.

Lightly preshape in a boule and let a 15 minute bench rest.

Shape it in a boule and ferment for abour 2 hours or so at a warm room temperature 22-24 degrees celsius.

Bake it starting at 250 with steam for 15 minutes and continue baking without steam for 40 minutes more at 225-230 until golden dark brown crust have reached.