01 - In a large mixing bowl, whisk together the gluten-free flour, sugar, yeast, and salt until thoroughly combined.
02 - Add the warm water, vegetable oil, and apple cider vinegar to the dry ingredients. Mix until a sticky, uniform dough forms.
03 - Gently fold in the blueberries using a light hand to avoid crushing the fruit and discoloring the dough.
04 - Lightly oil your hands and shape the dough into a smooth ball. Cover the bowl with a clean towel and let rise in a warm, draft-free spot for 45 minutes or until slightly puffy.
05 - Preheat your oven to 425°F. Line a baking sheet with parchment paper and set aside.
06 - Dust your work surface with a small amount of gluten-free flour. Divide the risen dough into 8 equal pieces.
07 - Roll each portion into a smooth ball, then poke a hole through the center with your finger. Gently stretch and shape into an even bagel ring. Place on the prepared baking sheet.
08 - Bring 2 quarts of water to a gentle boil in a large pot. Stir in the honey or maple syrup if using.
09 - Carefully drop 2-3 bagels at a time into the simmering water. Boil for 30 seconds per side, then remove with a slotted spoon and return to the baking sheet.
10 - Brush each boiled bagel with beaten egg and sprinkle with coarse sugar for a glossy, sweet finish.
11 - Bake for 20-22 minutes until golden brown and firm to the touch. Transfer to a wire cooling rack and let cool completely before slicing.