01 - Whisk together gluten-free flour blend, sugar, instant yeast, and salt in a large mixing bowl until thoroughly combined.
02 - Pour warm water, vegetable oil, and apple cider vinegar into the dry ingredients. Mix vigorously until a sticky, uniform dough forms.
03 - Gently fold blueberries into the dough using a spatula, taking care not to crush or bruise the berries.
04 - Lightly oil hands, shape dough into a smooth ball, and place back in bowl. Cover with a clean towel and let rise in a warm area for 45 minutes until slightly puffy.
05 - Set oven to 425°F and line a baking sheet with parchment paper.
06 - Dust work surface with gluten-free flour. Divide dough into 8 equal portions. Roll each into a ball, press thumb through center to create a hole, and gently stretch into bagel shape. Arrange on prepared baking sheet.
07 - Bring 2 quarts of water to a gentle boil in a large pot. Stir in honey or maple syrup if using.
08 - Carefully lower 2-3 bagels into boiling water. Cook for 30 seconds per side. Remove with slotted spoon and return to baking sheet. Repeat with remaining bagels.
09 - Brush each bagel with beaten egg wash if desired and sprinkle with coarse sugar.
10 - Bake for 20-22 minutes until golden brown. Transfer to wire rack and cool completely before slicing.