To achieve the choc layers, firstly spread the dough with chocolate mixture, then roll it. Use your fingers to gently lift one long edge of dough, then slowly move your fingers along the dough as you roll.
Chill the dough after rolling it into a log, then use a large sharp knife to cut the dough lengthways down the centre. This exposes the chocolate layers and gives you two even portions to work with.
Just like tsoureki (Greek Easter Bread), babka is shaped before baking. For an impressive finish, make sure the chocolate layers are facing up as you twist the two portions around each other.
Baking the babka in a loaf pan gives in height, which results in a light, fluffy centre. Place the twisted dough in the prepared pan and set it aside for 30 mins to prove before baking.