In the bowl of a stand mixer, combine all the ingredients: all purpose flour, corn flour, polenta, fresh yeast, salt, olive oil, grated parmesan cheese and 200ml water. Mix on low speed with the dough hook attachment until combined for about 5 - 10 minutes. Remove from the bowl, wrap in a cling film and place in a fridge for at least 2 hours.
preheat your oven
When the dough is ready, remove it from the fridge, preheat your oven to 220°C / 425°F and line 2 or 3 baking sheets with parchment paper.
roll the dough
Roll the dough out to a flat rectangle about 0.5 cm / 0.2 inch thick. Cut the rectangle in half and slice thin pieces from the short length of the rectangle with a sharp knife or a pizza cutter. Roll each piece into a long stick and place on the baking sheet. Continue with the remaining dough, placing the dough 1/2 inches apart.
Place the baking sheets into the oven and bake for 12 to 15 minutes. Keep an eye on them so they don't burn, as they are quite thin. Optional: Open the oven door after 10 minutes to release the steam for extra crispiness.
Move the grissini to a cooling rack to cool. Once they are completely cool, store them in an airtight container for up to 1 week. Enjoy.