1½ cups King Arthur Gluten-Free Multi-Purpose flour
2 tablespoons buttermilk or nonfat dry milk powder
1 tablespoon sugar or honey
1 teaspoon baking powder
¾ teaspoon salt
1 teaspoon xanthan gum
1 ½ teaspoons instant yeast
1 cup warm water
2 tablespoons olive oil (for dough)
2 tablespoons olive oil (parchment or pan)
Place the dry ingredients (except yeast) into a large mixing bowl; the bowl of your stand mixer is perfect. Mix until thoroughly blended.
Place the warm water, olive oil, yeast and about ½ cup of the dry mixture into a small bowl. Stir to combine; a few lumps are OK. Set aside for 30 minutes or so, until the mixture is bubbly and smells yeasty.
Add this mixture to the dry ingredients, and beat on medium-high speed for 4 minutes. The mixture will be thick and sticky; if you've ever applied spackling compound to a wall, that's exactly what it'll look and feel like. Note: you must use a stand mixer or electric hand mixer to make this dough; mixing by hand doesn't do a thorough enough job.
Cover the bowl, and let the dough rest for 30 minutes or so.
Preheat the oven to 425°F.
Drizzle 2 tablespoons olive oil onto the center of a baking sheet or 12-inch round pizza pan. Scrape the dough from the bowl onto the puddle of oil.
Using wet fingers, start at the center of the dough and work outwards, pressing it into a 12-inch to 14-inch circle.
Let the dough rest, uncovered, for 15 minutes.
Bake the crust for 8 to 10 minutes, just until it's set; the surface will look opaque, rather than shiny.