Combine Dry Ingredients: In the bowl of a stand mixer fitted with the paddle attachment, place the flour, xanthan gum, salt, cream of tartar, and sugar. Whisk to combine well. Add the yeast and whisk again.

Add Wet Ingredients: To the dry mixture, add the room-temperature yogurt, melted butter or ghee, beaten egg with egg white, and warm water. Mix on low speed until the ingredients are just combined.

Mix the Dough: Once the water is absorbed, increase the mixer speed to medium and mix for about 3 minutes. The dough will be fluffy and thick, but will not form into a tight ball like traditional wheat dough.

First Rise: Turn off the mixer and use a spatula to scrape the dough from the sides of the bowl, pressing it gently into a ball. Place the dough in a greased bowl or container with a tight-fitting lid. For same-day use, let the dough rise in a warm, draft-free spot for about 45 minutes, or until it has nearly doubled. After rising, refrigerate for at least 15 minutes to make it easier to handle. Alternatively, you can refrigerate the dough for up to 5 days and work with it cold.

Shape the Naan: Turn the risen dough out onto a lightly floured surface and sprinkle it with more flour. Divide your dough into 8 equal pieces (about 100 grams each). Working with one piece at a time, flour it generously and shape it into a smooth round.

Roll the Dough: Use a rolling pin to roll the dough into an elongated oval approximately 3-by-5 inches and about ⅜-inch thick. If the dough seems fragile or tears, gather it back together, work in a bit more flour, and roll it again.

Cook the Naan: While shaping the dough, heat about 1 tablespoon of ghee or coconut oil in a cast-iron skillet over medium heat. Carefully lift one piece of shaped dough and place it in the hot skillet. Cook for about 30 seconds, until large blisters begin to form.

Flip and Finish: Flip the naan and cook until the underside is golden brown and starts to blister. Flip it once more and cook for another 45 seconds, or until browned all over.

Keep Warm: Remove the cooked naan to a plate lined with a paper towel or tea towel and cover to retain heat and moisture. Repeat with the remaining dough, adding more fat to the skillet as needed. Stack the finished naan on top of one another and keep them covered until ready to serve.