In a mixing bowl, combine the warm water, instant yeast, and sugar. Let it sit for about 5 minutes until it's frothy.
Stir in the salt and gradually add the unbleached bread flour. Mix until the dough begins to come together.
Turn the dough onto a lightly floured surface and knead for about 8-10 minutes until it’s elastic and smooth.
Place the kneaded dough in a lightly oiled bowl, cover it with a damp cloth, and let it rise in a warm place for about 1 hour or until it has doubled in size.
Once the dough has risen, punch it down and divide it into 12 equal pieces. Roll each piece into a ball and poke a hole through the center to form the bagel shape.
In a large pot, bring water to a boil and add 1 tablespoon of sugar. Gently drop the bagels into the boiling water, cooking for about 1-2 minutes on each side.
After boiling, place the bagels on a baking sheet lined with parchment paper. Brush the tops with egg white and sprinkle with dried onion flakes.
Preheat your oven to 425°F (220°C) and bake the bagels for about 20-25 minutes, or until golden brown.
Once baked, transfer the onion bagels to a wire rack to cool. Slice and enjoy with your favorite toppings!