In a bowl, add the warm water, the egg, the sugar, the dry yeast powder and mix until the yeast and the sugar dissolve.
Next, add the wheat flour, the salt and mix again until the flour incorporates.
When you can no longer mix with the spoon, start kneading this mixture by hand until a smooth and uniform dough forms.
Now, add the unsalted butter at room temperature and knead again.
Add the white vinegar and knead until incorporated into the dough.
Cover the bowl and let it rise for 20 minutes.
After this indicated time, transfer the dough to a countertop and stretch it out into a rectangular shape making sure it’s not too thick nor too thin.
Next, add another tablespoon of unsalted butter at room temperature and spread it all over the dough.
Fold each edge of the dough towards the center, just like shown in the video and using a dough cutter, cut it into 6 equal pieces.
Now, roll each piece forming braided rolls – to do so, stretch out the dough, twist it and put the ends together, just like shown in the video.
Transfer these rolls to a baking tin lined with nonstick baking paper and brush one egg yolk over the rolls.
Also sprinkle black sesame seeds to taste all over these rolls.
Take to a preheated oven at 180°C (350°F) and bake for 40 minutes.
Serve.