Mixed flour (3000 grams of flour; 3000 grams of black powder; 3,000 grams of bread flour), water, S500(300 grams) and yeast, slowly stir together for 2 minutes, add salt, and stir at a medium speed to beat the gluten to the swelling stage.

Second step

The dough temperature is 25℃, and the dough is fermented for 2.5-3 hours.

Third step

The dough is divided into 600g pieces, which are proofed 1 hour.

Fourth step

Cut the bagel into the required shape with a blade, put it in a furnace at 250℃ and bake (steam) 15 minutes, then turn off the fire and bake for 25 minutes.