1. 1. Activate the Yeast: In a large mixing bowl, combine the warm water, active dry yeast, and granulated sugar. Stir gently and let it sit for 5-10 minutes until the mixture becomes foamy. This foaminess indicates that your yeast is active and ready to work.

2. 2. Combine Wet Ingredients: Add your active gluten-free sourdough starter, olive oil, and apple cider vinegar to the foamy yeast mixture. Whisk everything together until well combined. The mixture will look slightly cloudy.

3. 3. Mix Dry Ingredients: In a separate medium bowl, whisk together the gluten-free all-purpose flour blend, gluten-free oat flour, tapioca starch, and salt. Ensure there are no lumps and the ingredients are evenly distributed.

4. 4. Form the Dough: Gradually add the dry ingredient mixture to the wet ingredients, mixing with a sturdy spoon or a stand mixer with a paddle attachment on low speed. Continue mixing until a thick, sticky dough forms. Gluten-free dough will not be elastic like wheat dough; it will be more like a very thick batter.

5. 5. First Rise: Lightly grease a 9×5-inch loaf pan with olive oil. Transfer the dough into the prepared loaf pan, smoothing the top with a wet spatula. Cover the pan loosely with plastic wrap or a clean kitchen towel. Place it in a warm, draft-free spot for 60-90 minutes, or until the dough has risen by about 50-75% and looks visibly puffier. It won’t double in size like traditional bread.

6. 6. Preheat and Bake: While the dough is rising, preheat your oven to 375 F (190 C). Once risen, remove the cover from the loaf pan. Bake for 40-50 minutes, or until the crust is golden brown and a wooden skewer inserted into the center comes out clean. The internal temperature should register around 200-210 F (93-99 C) when fully baked.

7. 7. Cool Completely: Once baked, immediately remove the bread from the loaf pan and place it on a wire rack to cool completely. This is a critical step for gluten-free bread; slicing it warm can result in a gummy texture. Allow it to cool for at least 30 minutes, preferably longer, before slicing.