In a large bowl, place the all purpose gluten free flour blend, xanthan gum, tapioca starch/flour, baking powder, and salt, and whisk to combine.
Add the coconut oil, and toss it in the dry ingredients. With the tines of a large fork, break up the fat into small pieces so the mixture looks sandy.
Create a well in the center of the mixture, add the water, and mix to combine. The dough should be thick. If there are any crumbly bits at all, mix in more water slowly by the drop.
Knead the dough together and press it into a ball, cover with a moist tea towel or plastic wrap, and allow to sit for 20 to 30 minutes. The dough will stiffen a bit as it absorbs more of the water. You can also let it rest, covered in plastic, in the refrigerator for up to 3 days for easier handling.
Shape the dough
Sprinkle a flat workspace liberally with tapioca starch. Place the first piece of dough on top, and sprinkle again with more tapioca. Spread the tapioca all around the dough.
Use a knife or bench scraper to divide the dough into four equal pieces. Work with one piece of dough at a time, and cover the rest with a moist tea towel or plastic wrap to prevent them from drying out.
Work with piece of dough at a time, use a rolling pin to roll out the dough about ¼-inch inch thick.
If the dough seems smooth, proceed with the next step. If it doesn't seem smooth, but instead has what appears to be cracks, gather the dough together again, sprinkle with more tapioca starch, and roll it out again until it appears smooth.
Roll the dough, sprinkling with more tapioca and moving the dough frequently to prevent it from sticking or tearing, a bit more than 1/8-inch thick and at least 9-inches in diameter (to make 8-inch rounds).
Using a cake cutter or freehand with a pizza wheel or sharp knife, cut out a round approximately 8-inches in diameter. You'll cut one 8-inch round from each of the original 4 pieces of dough.
Gather the scraps and set them aside with the other pieces of remaining dough. You will reroll scraps together after you've worked with at least 2 pieces of dough.
Sprinkle each raw shaped tortilla with extra tapioca and stack them on to of one another as you work.
Cook the tortillas
Heat a 10- or 12-inch cast-iron skillet (or a nonstick skillet over medium heat) over medium-high heat. The skillet should be hot enough to sizzle when you drip water on it.
Place one round one at a time in the center of the hot skillet. Cook on one side until bubbles begin to appear on underside (about 45 seconds).
Using a wide spatula, flip the tortilla over, and cook on the other side until more bubbles form and the tortilla is dry (about another 30 seconds).
As it cooks, press down on the top of the tortilla to help it sear a bit, and cook it on the first side again if necessary. Remove the tortilla from the pan, place on large tea towel or in a tortilla warmer, and cover.
Repeat the process with the remaining pieces of dough, including gathering and rerolling all the scraps together.
You will make up to 2 more 8-inch tortillas from the scraps for a total of 6, 8-inch tortillas.
Make-ahead instructions
If you don’t plan to use the tortillas right away, place them, still wrapped in the towel, in a plastic bag to seal in moisture. Serve the tortillas within a few hours.
To freeze the tortillas, allow them to cool completely to room temperature.
Stack them, wrap tightly with freezer-safe wrap, and freeze until you're ready to use. Allow to defrost at room temperature and refresh in a hot, dry skillet before serving.
Video
Notes
Flour blends.My favorite gluten free flour blends are Better Batter's original blend gluten free flour and Nicole's Best multipurpose blend (with added xanthan gum). Bob's Red Mill 1-to-1 Gluten Free Baking Flour should also work, but add an additional 1/2 teaspoon xanthan gum to the dry ingredients or the dough won't hold together very well.Cup4Cup changed its formula and doesn't seem to work as well as it has in the past, so I don't recommend it. To make your own blend using one of my “mock” recipes, please see the all purpose gluten free flour blends page.Tapioca starch.This is one of the flours in all good gf flour blends, but you still need to add more here. You may be able to use glutinous rice flour (also called sweet white rice flour) in its place. If you have Expandex modified tapioca starch and would like to use that instead, you'll need 1 3/4 cups (245 grams) all purpose gluten free flour (1/4 cup more) plus 35 grams Expandex. For shaping the tortillas, use more of the flour blend (not Expandex).Nutrition information.Nutrition information is an estimate, per tortilla assuming the recipe makes a total of 6 8-inch round tortillas total.