Put water, milk, sugar and yeast in a bowl, mix and leave for 10-15 minutes for the yeast to get activated.
When the yeast is activated, add salt, oil, polenta and about 300g of Mix B flour and mix everything well with an electric mixer.
Gradually add the rest of the flour (250g) and stir until everything is well mixed into the liquid dough.

Sprinkle the remaining 50g of flour for mixing on the work surface and put the dough over it.
Knead the dough in a circular motion, combining it with the flour from the work surface. Do not press the dough too much so that it does not stick again and again.
The final density of the dough should not be too hard, but not too soft and sticky.

Flour a rattan dish or some other wooden dish and put shaped bread in it. Leave the dough to rise, about 20 minutes.
When the dough rises enough, transfer it to a baking tray lined with baking paper, coat with milk and olive oil and bake for about 30 minutes at 220ºC.
Transfer the finished bread to the rack to cool well and only then put it in a bag or bread box.