FOR THE BAO
Mix the flour, granulated sugar, dry yeast and salt in a large bowl.
Make a hole in the center and pour in the milk, oil, rice vinegar and a little water. Start working with the fork and slowly add the remaining water. If the dough is too stiff add a few more drops a little at a time. Set the dough out on a lightly floured work surface covered with a bowl and then knead for 10-15 minutes, or until smooth to the touch. Grease a bowl and place it inside. Cover with a damp cloth and let rise for about 2 hours, or until almost doubled in volume. Deflate the dough, cut it into 8 wedges and shape into balls.
Roll out one ball at a time into an oval shape about 3/4 mm thick. Then brush it with oil, fold it by inserting a piece of parchment paper in the middle to prevent the two halves from sticking together during cooking. Transfer the sandwiches to a baking tray, cover them with a clean tea towel and let them double in size (it is better in the oven off).
Steam for about 10 minutes (or in the steam oven) using parchment paper with holes under each crescent. They should be puffy and very soft.
FOR THE AIOLI SAUCE
Place the eggs in a saucepan and cover with cold water and bring to the boil. From the boil it counts about 7 minutes.
Once boiled, empty out the hot water and fill the pot with cold water. Once cold, shell them and cut them into small pieces. Pour everything into the mug of an immersion blender or a jar, combine the garlic cloves without the core, the salt and add the filtered juice of half a lemon.
Start working with the immersion mixer by moving it up and down and, in the meantime, slowly pour in the extra virgin olive oil.
Once it's swollen and fluffy add a grind of pepper. Store in the refrigerator covered in contact film.
FOR THE DUCK BREAST
Incise the skin of the duck by making parallel cuts in both directions: you will have to obtain a sort of grid.
Season with pepper. Arrange it in a large dish and pour all the ingredients. Massage it well, then cover it with contact film and leave to marinate for a few hours. At the end, filter the marinade juices and dry the breast by dabbing it well with paper.
Place the breast upside down (skin side down) on the bottom of a cold frying pan, then place over the heat (in doing so the fat will melt without burning).
Cook for about 5/7 minutes on the skin side, then turn over and brown over low heat for another 3/4 minutes.
During cooking you can brush the skin with the marinade made by mixing all the remaining ingredients.
At the end, place in the oven for 5/8 minutes at 200° C (depending on the size) with the skin facing upwards so that it caramelises.
Once out of the oven, place the breast on a cutting board, lifting it with two wooden ladles. Let cool. It should be pink in the center.
The cooking juices can be reduced over the heat thus obtaining a syrupy sauce to be used to lacquer the duck before filling the sandwich.
Cut the breast diagonally into slices of about 3/4 mm.
TO STUFF THE SANDWICH
a bunch of fresh coriander
semi-hot red chillies
Sesame seeds
Slightly open the baos, measure a spoonful of aioli inside, arrange two slices of duck breast. Add some sesame seeds, a few fresh coriander leaves and a little chopped chilli pepper.
