Scale all ingredients.
Use a professional mixer, place starter and water in the mixing bowl and mix for 1 minute to break the starter apart.
Add in the rest of the ingredients, mix at slow speed for 2 minutes. Switch to medium speed and continue mixing until gluten is fully developed.
Place dough in a slightly grease bowl, cover with plastic wrap or lid. Bulk fermentation for 3 hours at room temperature.
Divide and pre-shape into rounds of 125g. Rest 5-10 minutes.
Poke your finger in the middle of the rounds to make a hole and enlarge the hole.
Place on a parchment line paper and proof for 30 minutes.
10 minutes before the bagels are done proofing, measure out 1000 ml of water, 10 grams of baking soda, and 10 grams of sugar and put in a pot or bowl. Bring the water to boil.
Pre-heat the oven to 400 °F.
Boil 1-2 bagels at a time, 30 seconds on each side. Remove and place on a rack to drain excess water.
Dip bagels into toppings of choice, sesame seeds, poppy seeds, and other toppings.
Place on a parchment line paper tray and bake for 15 minutes at 400°F.
Remove and transfer the cooked bagels onto a wire rack and let it cool before serving.