Mix the starter/culture with the water in the mixer.
Add the remaining ingredients and mix on low (2nd puts strain on the motor) for 10 - 15 minutes or until gluten develops.
Remove dough from m mixing bowl and fold several times (as tolerated by the dough).
Allow dough to ferment for at least 3 hours, folding hourly. (if using a proofing box, 78 degrees F works well).
Preheat your oven to 500F. Start heating a large pot of water You can add some malt syrup or honey to the water.
Divide the dough into 48 pieces, these will be 150g each.
Shape each into a tight ball and allow to rest for 15 minutes.
Shape the balls into bagels by pinching your thumb and index finger into the middle of the dough ball. Insert both of your index fingers into the hole and rotate them around each other, stretching out the dough. Allow bagels to rest 15 minutes.
If using seeds on the bagels, add 2 Tablespoons of corn starch to 2 cups of cold water in a small pot and bring to a boil. Remove from heat and prepare dishes of the seeds you wish to use.
By now your water should be boiling or close to it. Place bagels into the boiling liquid.
Allow bagels to simmer for 30 seconds. If using seeds, this is when you'd start painting the tops of the bagels with the boiled corn starch liquid.
Turn the bagels and allow to simmer another 30 seconds. If using seeds, this is when you would dip each bagel into your dish of seeds. Place the bagels on a tray or board to await baking.
Repeat the process until all bagels have been boiled.
Bake in oven in batches. Each batch should take 12 - 17 minutes. If using convection, start at 10 minutes and give at least 2 more minutes. Bagels should be golden brown when done. If using seeds, The tops may appear as if undone. In that case, you can check with an instant read thermometer. They're fully baked at 200F.