Oil two 13-inch pizza pans or baking sheets, using olive oil. In the bowl of a stand mixer, combine the flours, xanthan gum, salt, yeast, and sugar. In a measuring cup, combine the water and 3 tablespoons olive oil. Add olive oil-water mixture to dry ingredients, then egg whites, mixing well after each addition. Beat on high speed for 4 minutes.
Divide dough into two (four or six) equal portions. Place each portion on a prepared pizza pan.
Drizzle about a tablespoon of olive oil over your hand and one portion of dough. I usually pat the dough back and forth in my hand until rounded.
Spread the dough out evenly over the pizza pan, forming a ridge around the edge to contain the pizza toppings. Repeat process for second portion of dough. Let dough rise for about 20 minutes.
Preheat oven to 400 degrees F. Bake pizza crusts for 7 minutes (or until lightly golden) and remove from oven. At this point you can either cool the crusts, wrapping and freezing them for future use. If you would like pizza right away, top the risen crusty with tomato sauce and top with your favorite toppings.