Take all the products out to room temperature. Heat the milk, set aside 2/5 cup (100 ml) of it in a bowl, add the sugar, yeast and a little flour. Stir until you obtain a thick mixture, cover with a plate and leave it to activate. Set aside 1 of the yolks, beat the other eggs and egg white with the milk, yoghurt and oil.
Sift the flour 3 times, make a well and mix both mixtures well while constantly stirring in the flour, then knead a smooth dough. Put it in an oiled bowl, cover with foil. Later, divide the dough into 4 parts, make 2 of them a bit larger, as well as 1 small part about the size of a walnut or apple.
Roll out the 2 smaller parts into 2 sheets, smear 1 with butter and wrap into a roll, cut the other sheet into thin strips in the middle and weave them together in pairs. Place the woven sheet on top of the roll.
Repeat this process for the 2 larger sheets, put baking paper in the baking tray and fold both parts to make an 8 shape.
Roll out the small bit of dough into a sheet, cut out circles, shape the rose and leaves. Use a sharp knife to form the leaves, arrange them wherever you like.
Leave the loaf to rise, then smear with the beaten egg yolk, sprinkle sesame seeds and bake in a preheated 338°F (170 °C) oven about 35 min.