Ensure your gluten-free sourdough starter is active and ripe. Feed it 4-12 hours before you plan to mix your dough, ensuring it's at its peak — bubbly, doubled in size, and passes the float test (a small spoonful floats in water).

In a large mixing bowl, combine the warm water and psyllium husk powder. Whisk well and let it sit for 5-10 minutes until it forms a thick gel. This is crucial for gluten-free dough structure.

Add the active gluten-free sourdough starter to the psyllium gel mixture and mix until well combined.

In a separate bowl, whisk together the brown rice flour, sorghum flour, tapioca starch, potato starch, and fine sea salt until thoroughly combined.

Add the dry flour mixture to the wet starter-psyllium mixture. Use a sturdy spoon or your hands to mix until all the flour is hydrated and a shaggy dough forms. It will be thick and sticky.

Cover the bowl with a damp cloth or plastic wrap and let it rest for 30 minutes. This allows the flours to fully hydrate.

Perform the first set of stretch and folds: Wet your hands slightly or lightly coat them with olive oil. Gently grab a portion of the dough from the side, stretch it upwards, and fold it over to the center. Rotate the bowl and repeat this 3-4 times until you've gone all around the dough. The dough will feel sticky but should start to gain some elasticity.

Cover the bowl and let the dough rest for 30-45 minutes.

Repeat the stretch and fold process three more times, with 30-45 minute rests in between each set. By the final set, the dough should feel smoother, more cohesive, and slightly more resilient.

After the last set of stretch and folds, cover the bowl and let the dough bulk ferment at room temperature (around 70-75°F / 21-24°C) for 3-6 hours. The exact time will depend on your starter's activity and room temperature. Look for the dough to increase in volume by about 20-30% and show some small bubbles on the surface.

Lightly flour your work surface with gluten-free flour. Gently scrape the dough out of the bowl onto the floured surface. The dough will still be soft and somewhat sticky.

Pre-shape: Gently pat the dough into a loose circle or rectangle. Then, gently fold the top third down to the center, the bottom third up over that, and then fold in the sides to form a somewhat tight ball or log. Let it rest, seam-side down, for 20 minutes, uncovered, to relax the gluten-free structure.

Final shape: Lightly flour your hands and the dough. Gently flip the dough seam-side up. Shape it into a taut boule (round) or batard (oval) by using your hands or a dough scraper to create tension on the surface. You want to create a smooth, tight skin on the outside.

Generously flour your banneton basket (or a bowl lined with a floured tea towel). Carefully transfer the shaped dough, seam-side up, into the banneton.

Cover the banneton with plastic wrap or a shower cap and refrigerate for 8-16 hours (or up to 24 hours). Cold proofing develops flavor and makes the dough easier to handle and score.

Preheat your oven to 450°F (232°C) with your Dutch oven inside for at least 30-45 minutes. This ensures the Dutch oven is scorching hot.

Carefully remove the hot Dutch oven from the oven. Gently invert the cold dough onto a piece of parchment paper. Score the top of the dough with a lame or sharp knife (e.g., a single deep slash or a decorative pattern).

Using the parchment paper as a sling, carefully lower the dough into the hot Dutch oven. Cover with the lid.

Bake covered for 30 minutes.

Remove the lid and continue baking for another 20-25 minutes, or until the crust is a deep golden brown and sounds hollow when tapped on the bottom. An internal temperature of 200-210°F (93-99°C) is ideal.

Carefully remove the loaf from the Dutch oven and transfer it to a wire rack to cool completely for at least 2-3 hours before slicing. Slicing too early will result in a gummy texture.