In a small bowl, combine the warm water, yeast, and sugar. Stir gently and let sit for 5 to 10 minutes until the mixture is foamy.
In a large mixing bowl, whisk together the King Arthur Gluten Free Flour Blend, xanthan gum, and salt.
Add the foamy yeast mixture, olive oil, and apple cider vinegar to the dry ingredients.
Using a stand mixer fitted with a paddle attachment or a hand mixer, mix on medium speed for about 3 to 5 minutes until the dough is smooth and slightly sticky.
Lightly grease two 12-inch pizza pans or baking sheets with olive oil.
Divide the dough in half and transfer each portion to a prepared pan.
Using wet hands or a spatula, gently press and spread the dough evenly across each pan to form a thin crust about 1/4 inch thick.
Cover the dough loosely with plastic wrap or a clean kitchen towel and let it rest in a warm place for 15 minutes to slightly rise.
Preheat the oven to 425°F (220°C).
Remove the cover and bake the crusts for 10 minutes until they begin to set and slightly brown.
Remove the crusts from the oven, add your desired toppings, and bake for an additional 10 minutes or until the crust is golden and the toppings are cooked.
Let the pizzas cool for 5 minutes before slicing and serving.