Combine warm water, sourdough discard, and yeast. Add flour and salt and stir together with a wooden spoon or dough whisk. Once dough has formed into a "shaggy dough," meaning all the flour is incorportated but it's not smooth.
Let rest for 10-25 minutes. Turn out onto a floured surface and knead the pizza dough for 2-3 minutes, until smooth.
Divide dough into four pieces for four 8 inch pizzas. Cover and let rise for 2-4 hours.
Preheat oven to 450 degrees. I like to use my cast iron pizza pan or you can use a pizza stone. If you are using a cast iron or pizza stone, place that in the oven while the oven is preheating.
When the pizza balls have risen about double, shape them into four pizzas and place them on parchment paper. Top with your favorite sauce and toppings.
Once oven is a correct temperature, place your pizza (with parchment paper under it) one at a time on your prepared pan. Cook for 6-7 minutes.