In a large mixing bowl (or the bowl of a stand mixer), combine the warm water, yeast, and 2 tablespoons of sugar. Stir gently and let it sit for 5-10 minutes, until foamy. This indicates the yeast is active.

Add the bread flour and salt to the yeast mixture. If using a stand mixer, attach the dough hook and mix on low speed for 8-10 minutes until the dough is smooth, elastic, and pulls away from the sides of the bowl. If mixing by hand, stir with a wooden spoon until a shaggy dough forms, then turn it out onto a lightly floured surface and knead for 10-15 minutes until smooth and elastic.

Gently fold in the blueberries. Try not to overmix, as this can break the blueberries and stain the dough too much. Mix just until they are evenly distributed.

Lightly grease a clean bowl with oil. Place the dough in the bowl, turning once to coat. Cover the bowl with plastic wrap or a clean kitchen towel and let it rise in a warm place for 1 to 1.5 hours, or until doubled in size.

Gently punch down the risen dough and turn it out onto a lightly floured surface. Divide the dough into 8 equal pieces (approximately 110-120g each).

To shape each bagel: Roll each piece of dough into a smooth ball. Then, either poke a hole in the center of each ball with your thumb and gently stretch it to create a 1-inch hole, or roll each piece into a 9-inch rope, flatten the ends, and pinch them together to form a ring.

Place the shaped bagels on a baking sheet lined with parchment paper. Cover loosely with plastic wrap and let them rest at room temperature for 20-30 minutes. Meanwhile, preheat your oven.

Preheat your oven to 425°F (220°C). Line two baking sheets with parchment paper.

In a large pot, bring 8 cups of water to a rolling boil. Add 2 tablespoons of sugar (or barley malt syrup) and the optional baking soda. Reduce heat slightly to a gentle boil.

Working in batches of 2-3 bagels, carefully drop the bagels into the boiling water. Boil for 1 minute on one side, then flip them over with a slotted spoon and boil for another 1 minute on the other side. For a chewier bagel, you can boil for up to 2 minutes per side.

Remove the bagels with a slotted spoon, allowing excess water to drain off. Place them on the prepared baking sheets.

If desired, brush the tops of the boiled bagels with the beaten egg white for a shiny crust.

Bake for 18-25 minutes, rotating the sheets halfway through, until the bagels are golden brown and cooked through.

Transfer the baked bagels to a wire rack to cool completely before slicing and serving.