Mix the flour, sugar and salt. In a separate bowl, whisk together water and biga until biga is dissolved. Pour in the flour mixture and mix quickly. (Dough will look bumpy and stringy.j cover the bowl and let rest for 20 minutes. Dust the edges with flour and fold them onto the center of the bowl. Turn dough over, cover, and let sit at room temperature for 5 to 7 hours, until increased in size by a third and visibly bubbly.
Dust flour over two 12 by 16 pieces of parchment paper. Sift a little flour over the dough and flour your hands. Using a scraper, divide dough in half. Pinch off one half and form into a taut ball and place seam side down on one piece of the parchment paper. Repeat with the second half of parchment.
Lightly brush olive oil over the tops of the dough rounds, leaving a 2 inch margin. Let rounds sit, uncovered until doubled in size, 1 to 3 hours.
Place a pizza stone on the middle rack of the oven and heat to 500 degrees. (Or use sheet pans to cook pizza. Try preheating them with the oven too.)
Dust the tops of the dough with a little flour and gently pull outward with both hands so that it stretches to about 8 inches. Dock the dough.
Place on pizza peel and stretch out to about 12 inches. Dock again.
Add desired toppings.
Slide pizza onto pizza stone or hot pan. Lower temperature to 450 degrees and bake for 20 to 25 minutes.