First, in a large mixing bowl, combine the bread flour, instant yeast, and salt. Mix well.
In a separate bowl, mix together the warm water and maple syrup or agave nectar until the sweetener is dissolved.
Pour the liquid mixture into the dry ingredients. Stir until a dough forms.
Transfer the dough to a lightly floured surface and knead for about 10 minutes, until the dough becomes smooth and elastic.
Shape the dough into a ball and place it in a lightly oiled bowl. Cover the bowl with a clean kitchen towel or plastic wrap and let the dough rise in a warm place for about 1 hour, or until it doubles in size.
Preheat your oven to 425°F (220°C) and line a baking sheet with parchment paper.
Punch down the risen dough and divide it into 8 equal pieces. Shape each piece into a ball and use your thumb to poke a hole in the center. Gently stretch the hole to form a bagel shape. Repeat with the remaining dough.
In a large pot, bring the 12 cups of water and maple syrup or agave nectar to a boil.
Carefully drop 2-3 bagels into the boiling water. Boil them for about 1 minute on each side, then remove them with a slotted spoon and place them on the prepared baking sheet.
If desired, sprinkle the bagels with sesame seeds, poppy seeds, or coarse salt.
Once all the bagels have been boiled and topped, bake them in the preheated oven for 20 to 25 minutes, or until they turn golden brown.
Remove the bagels from the oven and let them cool on a wire rack.
Finally, slice the bagels in half and toast them before serving.