Preheat your oven to 350°F (175°C). Line a standard 9-inch x 5-inch loaf pan (or smaller) with unbleached parchment paper, leaving some overhang for easy removal. Set aside. Alternatively, line a standard 12-cup muffin tin with liners and set aside.
Make the Pizza Dough: In a large bowl, whisk together the gluten-free flour blend, xanthan gum, baking powder, and salt. Add the yogurt and 3 tablespoons of water, mixing until the dough holds together well. If the dough feels too stiff, add more water, one tablespoon at a time, until it clumps and holds together without being too sticky.
Turn the dough onto a lightly floured surface, sprinkle with more flour, and knead until it’s smoother. Roll the dough into a rectangle about 1-inch thick using a rolling pin. Use a small, round cookie cutter (about 1-inch in diameter) to cut out rounds of dough. Re-roll the scraps as needed.
Roll the Dough in Cinnamon Sugar: In a small bowl, mix the granulated sugar, cinnamon, and salt. Dip each dough round into the melted butter, allowing excess butter to drip off, then coat it in the cinnamon sugar mixture. Place each coated dough ball into the prepared loaf pan or muffin tin. If using a loaf pan, create a single, even layer of dough balls and continue layering until you reach the top of the pan. For a muffin tin, place about 5-6 dough balls in each well.
Bake the Monkey Bread: Place the loaf pan on a baking sheet to catch any drips and bake in the preheated oven until the monkey bread is lightly golden and firm to the touch, about 25 minutes for a loaf pan and 20 minutes for a muffin tin. Remove from the oven and let cool in the pan for at least 30 minutes.
Make the Glaze: In a small bowl, combine the confectioners’ sugar and 1 tablespoon of milk, stirring until a thick paste forms. Add more milk, 1/4 teaspoon at a time, until the glaze is thick but pourable. Drizzle the glaze generously over the cooled monkey bread and serve immediately.