Combine the water, yeast, and 3 tablespoons of the sugar in a let stand for about 5 minutes. Add to salt and flour. Knead dough until smooth and elastic. Add additional flour, if necessary. Lightly coat dough with oil and let rise for about 1 hour.
Preheat the oven to 200 F (400 C). Sprinkle a baking sheet with semolina flour (or cornmeal).
Portion dough into 50 g pieces. Shape into balls. Pierce with spoon handle and create very large holes for bagels. (Holes will close while cooking if not made big enough.)
In a large, heavy pot, bring 12 cups of water and 1 tablespoon of sugar to a boil. For salty bagels, boil bagels in a large pot with 1 tablespoon of baking soda instead of sugar. Boil bagels, dropping only a few at a time. Ensuring that bagels are fully submerged, cook each bagel for no more than 20-30 seconds. Put on plate immediately after boiling. Optionally, add toppings on face-down sides, such as poppy seeds or sesame seeds.
Bake bagels in oven on parchment paper lined baking pan or directly on pizza stone, then flip over and cook for 30 to 35 minutes, or until golden brown in color.