To prepare the biga, combine the flour with water and yeast. Using your fingertips, mix coarsely until all water is absorbed. (Note: The dough should not be too compact.) 

Rest at room temperature in a container covered with a clean cloth for 16 hours.

In a large bowl, mix 100 grams of water with the crumbled biga.

Add the flour, mix well, then remove from the bowl and knead with your hands on a hard surface for 6 to 7 minutes.

Return the dough to the bowl; add the salt and the remaining 20 grams of water. Continue kneading for 7 to 8 minutes.

Divide the mixture into 4 equal dough balls (about 140 grams each); cover with a clean cloth and proof on a floured work surface for 6 hours. 

Form a rectangle from one ball of dough by rolling it out to roughly 10 inches by 6 inches (25 centimetres by 15 centimetres).

Tap a rolling pin into ¼ of the cold butter to flatten it into a smaller rectangle, about 6 inches by 3 inches (16 centimetres by 8 centimetres).

Place the butter on top of the dough and sprinkle with a quarter of the freshly grated  Parmesan. Fold the dough over it so no butter peeks out. 

Rest in the fridge for 30 minutes. 

Take the dough out of the fridge and roll it out again into an 8 inch by 12 inch (20 centimetre by 30 centimetre) rectangle about ¼ inch (6 millimetres) thick. 

Fold the two longer ends into the middle so they overlap. 

Let the dough rest in the fridge for 30 minutes.

Repeat the process of rolling the dough out into a rectangle and folding it in one more time.

Lightly flour your work surface and form into a 12-inch (30-centimetre) disc.

Slice the peeled onions into ¼ to 1 inch strips (1 to 2 centimetres thick). Add the water and onions to a saucepan, cover, and cook over medium heat until translucent, about 10 to 15 minutes. Stir occasionally. 

Spread 4 tablespoons of crème fraîche on the dough base, leaving about an inch (2 1/2 centimetres) around the edge for the crust. 

Sprinkle with a quarter of the Parmesan, then add a quarter of the cooked onions on top.

Preheat your Ooni oven, aiming for 300 °C (570 °F) on the centre of your baking stone. You can check this quickly, accurately and from a safe distance using an infrared thermometer.

Launch the pizza and turn off the gas (or close the baffle if you're using wood). Bake for 3 minutes in the residual heat, turning every 20 seconds to ensure an even bake.

As soon as the pizza is cooked, remove from the oven. Add slices of sausage and sprinkle with the sea beans.

Slice, serve and enjoy!

Repeat the steps for the remaining pizzas.