1. Pour the warm milk into a deep bowl, then add the sugar and yeast, stir, cover and let sit for 15 minutes. Then add oil, vinegar, salt, eggs, mix everything and gradually add flour. Knead a thin, sticky dough, then add the softened butter cubes and knead into the dough. Let the dough rest, covered, for 2 hours.
2. Divide the dough into 9 balls of 170 grams each. Place the balls on a baking tray, which you have lined with baking paper. When you have arranged all the balls, cover them with a kitchen towel and let them sit for 30 minutes.
3. Mix one egg yolk and 1 tablespoon of milk, cover the brioches and sprinkle with sesame.
4. Bake at 180 degrees, 20 minutes.
