Mix the gluten-free all-purpose flour, ground flaxseeds, baking powder, Italian seasoning, and salt in a large bowl.
Add water and olive oil, stirring to form a dough ball. If the dough is too dry, add more water a tablespoon. If it's too wet, add a little more flour.
Brush a piece of parchment paper with oil and place it on a rimless baking sheet (or invert a regular baking sheet). Flatten the dough with your hands, or cover it with another greased baking sheet and use a rolling pin to roll it into a 10-inch circle. Shape the edges to create a rim.
Preheat your oven to 400°F. Bake the pizza dough for 15 minutes or until the crust is slightly browned.
Add Toppings and Bake: Add your favorite pizza sauce and toppings, then bake for 15 minutes.