Make the Dough:

In a large bowl, combine all-purpose flour, salt, yeast, and warm water.
• Knead the dough on a floured surface for about 10 minutes until smooth and elastic.
• Cover the dough with a damp cloth and let it rise in a warm place until it doubles in size, about 1 hour.

Shape the Dough:

• After the dough has risen, punch it down to release air bubbles.
• Roll the dough into a long log and divide it into 21 pieces (each piece should weigh about 35 g).
• Roll each piece into a round wrapper, making the edges thinner than the center.

Fill and Seal:

• Place a spoonful of the filling in the center of each wrapper.
• Pinch the edges together to seal, forming a pleated baozi. Make sure the seal is tight to prevent it from opening during steaming.