Dissolve the dry yeast in the warm milk.

Sift the flour with the salt and sugar into a deep bowl. Pour in the milk with yeast, add the room-temperature butter. Knead the dough and leave in a warm place for 1 hour.

Divide the risen dough into 2 parts. To one, add the cocoa and vegetable oil and knead into a chocolate dough - you'll get two balls, one white and one chocolate.

Roll each ball into a sheet and stack one on top of the other. Roll up like a log: fold to the middle from the top and from the bottom.

Transfer the loaf to a baking sheet greased with vegetable oil and let it rise for another hour.

Bake in an oven preheated to 180-200 °C for 20-25 minutes (mine took 25 minutes). Cool on a rack - and enjoy. Bon appetit!