1. Activate the Yeast and Start the Dough: In a large mixing bowl, combine the warm water, granulated sugar, and active dry yeast. Stir gently and let it sit for 5-10 minutes until it becomes foamy, indicating the yeast is active. If it doesn’t foam, your yeast might be old, or the water wasn’t the right temperature; start again with fresh yeast. Add the sourdough discard to the foamy yeast mixture and stir well to combine.

2. Mix in Dry Ingredients: Gradually add 3 1/2 cups of the all-purpose flour, salt, and ground cinnamon to the wet ingredients. Mix with a wooden spoon or your hands until a shaggy dough forms. It will look a bit rough and sticky at this stage.

3. Knead the Dough: Turn the dough out onto a lightly floured surface. Knead for 8-10 minutes, adding more flour a tablespoon at a time if the dough is too sticky, until it’s smooth, elastic, and springs back when gently poked. This kneading develops the gluten, which is essential for that classic chewy bagel texture.

4. Incorporate Raisins and First Rise: Flatten the dough slightly and sprinkle the raisins evenly over the surface. Fold the dough over and continue kneading for another 1-2 minutes until the raisins are well distributed throughout the dough. Form the dough into a ball, place it in a lightly oiled bowl, turning once to coat, and cover with plastic wrap or a clean kitchen towel. Let it rise in a warm place for 1 hour, or until it has nearly doubled in size.

5. Shape the Bagels: Gently punch down the risen dough and divide it into 8-10 equal pieces. Roll each piece into a smooth ball. To shape the bagels, poke a hole in the center of each ball with your thumb and gently stretch the dough to create a 1-inch hole. Aim for an even thickness around the hole. Place the shaped bagels on a lightly floured baking sheet.

6. Boil the Bagels: Preheat your oven to 400 F (200 C). Bring a large pot of water to a rolling boil and add the baking soda. This helps create that signature shiny, chewy crust. Carefully drop 2-3 bagels into the boiling water at a time (don’t overcrowd the pot). Boil for 30 seconds on each side. Using a slotted spoon, remove the bagels and place them back on the floured baking sheet.

7. Egg Wash and Bake: Brush the tops of the boiled bagels with the lightly beaten egg white. This gives them a beautiful golden sheen. Bake for 20-25 minutes, or until golden brown and cooked through. Let them cool slightly on a wire rack before serving.