In a large bowl take 180 ml warm water. Add sugar and yeast. Add 1 cup all- purpose flour. Mix well. Cover the bowl and keep in a warm area for 3 hours.
Add remaining 1 cup flour and salt to sponge and stir well. Remove the dough from the bowl to the floured counter and knead by stretching and folding method (stretch the dough with the heel of the hands and fold it back with the fingers )
This helps gluten to develop. Knead for 8 to 10 minutes till dough becomes smooth, supple and elastic.
Make a boule (ball) and place it in a large bowl. Cover and keep in a warm place to rise for 1 to 1 ½ hours or until double in size.
Remove the dough carefully from the bowl without deflating it completely, into the counter. Cut the dough into three equal pieces. Form each piece into boule. Cover and let the balls rest for 10 minutes.
Gently flatten each boule, slap it gently into the counter 3 times. Flatten it again to get a rectangular shape. Roll it lengthwise and pinch the edges together. Place both hands on the rolled dough, roll it back and forth on the counter.
Applying more pressure on baby fingers than on your thumbs to shape it into a spindle shape roll – Banh mi.
Place the shaped roll on a piece of parchment paper and cover with a kitchen towel. Let it rest for 1 hour or until double in size.
Preheat the oven and the baking tray at 230 degrees C. Place a bowl of hot water at the bottom of the oven.
Slash the baguette with a sharp knife or a fresh razor blade. Keep the blade at 45 degree angle and make quick slash across the baguette. Bake immediately after slashing.
Remove the preheated tray, lift the parchment paper with the baguettes and transfer onto the tray. Spray water on the baguettes.
Bake for 20 to 25 minutes. After the first 8 minutes, spray some more water on the baguettes. Keep rotating the parchment sheet so that the baguettes turn golden evenly.
Turn off the heat and let the baguettes remain in the baking tray for 5 minutes. Remove from the oven. You can hear the crackling sound from the baguettes.
Let the baguettes cool before serving.