After 24 hours, the poolish should be bubbly and roughly doubled in size.
To make the main dough, move the poolish to your stand mixer bowl. Pour in the remaining 100ml of water and 0.9g of yeast. Set your stand mixer to low speed, and let it run for around 1 minute until the poolish is incorporated into the water.
Gradually add the remaining 500g of flour while the mixer is running on low speed until all the flour is incoperated and the dough starts to come togeter.
Let the mixer run at medium for 15 minutes.
Add the 25g of salt and let the mixer run for another minute.
Let the dough rest for 15-30 minutes to relax, then fold it up to a nice, round ball and cover the mixing bowl with plastic wrap or move it to an air-tight gonctainer, and let the dough bulk ferment fro 2 hours.
Move the dough to your countertop and divide into 6 dough balls of 250g.
Place the dough balls in a rising box and leave them to rise for 8 hours.