Step 1: Activate Yeast. In a small bowl, combine the warm milk (105-115°F / 40-46°C), 1 teaspoon of granulated sugar, and active dry yeast. Stir gently and let sit for 5-10 minutes until the mixture is foamy, indicating the yeast is active.
Step 2: Prepare Dry & Wet Ingredients. In the bowl of a stand mixer, whisk together the gluten-free all-purpose flour blend, the remaining 1/4 cup granulated sugar, and salt. In a separate bowl, lightly beat the 2 large eggs for the dough, then add them to the activated yeast mixture.
Step 3: Combine and Knead. Pour the wet ingredients into the dry ingredients in the stand mixer. Using the paddle attachment, mix on low speed until just combined. Gradually add the softened butter, one tablespoon at a time, mixing thoroughly after each addition until fully incorporated. Increase the speed to medium and beat for 5-7 minutes until the dough is smooth, elastic, and pulls away from the sides of the bowl. Gluten-free brioche dough will be softer than traditional dough.
Step 4: First Rise & Shaping. Lightly grease a large bowl. Transfer the dough to the bowl, cover with plastic wrap, and let rise in a warm place for 1.5 to 2 hours, or until doubled in size. Gently punch down the dough to release air. Shape the dough into a loaf and place it into a greased 9x5-inch loaf pan. Cover lightly with plastic wrap and let rise again for 45-60 minutes, or until nearly doubled in size.
Step 5: Bake the Brioche. Preheat your oven to 375°F (190°C). In a small bowl, whisk the remaining large egg with 1 tablespoon of water to create an egg wash. Gently brush the top of the risen brioche loaf with the egg wash. Bake for 30-35 minutes, or until the top is golden brown and a thermometer inserted into the center of the loaf reads 200-205°F (93-96°C). If the top begins to brown too quickly, loosely tent with aluminum foil. Let the brioche cool in the pan for 10 minutes before transferring it to a wire rack to cool completely.
Notes
Gluten-free doughs can be stickier than traditional doughs; resist the urge to add more flour during mixing. Chilling the dough for 30 minutes after the first rise can make it easier to handle for shaping. Store leftover brioche in an airtight container at room temperature for up to 3 days, or freeze slices for longer storage. This brioche is excellent toasted, as French toast, or for sandwiches.