In a large mixing bowl, combine warm water and active sourdough starter. Add bread flour and salt. Mix until a shaggy dough forms and no dry flour remains.
Turn the dough onto a lightly floured surface and knead for about 5 minutes, until smooth and elastic. You can also use a stand mixer with a dough hook.
Place the dough back in the bowl and let it rest for 45 minutes. Perform one stretch and fold, then let it rest again for another 45 minutes and repeat.
Cover the dough and let it rise in a warm spot for 4 to 6 hours, or until puffy and slightly doubled.
Turn the dough onto a floured surface and divide into 2 large dough balls or 4 smaller portions for personal pizzas.
Cover and let the dough rest at room temperature for 30 to 60 minutes to relax the gluten.
Preheat your oven to 475 degrees. Place a pizza stone or baking steel in the oven while it heats.
On a lightly floured surface, press and stretch the dough into a round. Leave a slightly thicker edge for the crust.
Transfer the dough to a piece of parchment paper. Add sauce, cheese, and your favorite toppings.
Use a pizza peel to transfer the pizza onto the hot surface. Bake until the crust is golden brown and the cheese is melted and bubbly.
Let cool for a few minutes, then slice and serve.