Method

• 1.
  Place yeast, milk and 1 tsp sugar in a small bowl and whisk with a fork to combine. Set aside for 15 minutes or until frothy.
• 2.
  Combine eggs, egg yolk, cinnamon, remaining 105g sugar and 1 tsp salt in a bowl. Place the flour in the bowl of an electric mixer fitted with a dough hook. Add the yeast and egg mixtures, then knead on medium speed until combined.
• 3.
  Reduce speed to low and knead for 10 minutes or until the dough is smooth and elastic. Add 125g butter, 1 piece at a time, until combined and the dough is smooth. Place the dough in a lightly greased bowl, cover with a clean tea towel and set aside in a warm place for 11/2-2 hours until doubled in size.

• 4.
  Grease a large 30cm x 12cm x 6cm deep loaf pan and line the base and sides with baking paper.
• 5.
  Knock back the dough, then roll out dough on a lightly floured surface to a 45cm x 30cm rectangle. Brush dough with remaining 25g butter, leaving a 2cm border, then scatter evenly with chocolate. Brush the long side closest to you with water to seal.
• 6.
  Working from the long edge closest to you, roll dough into a tight log, pinch to seal. Cut the dough lengthways to create two logs. Turn the halves cut-side out to expose chocolate, then twist two logs together and place in the lined loaf pan.
• 7.
  Cover with a clean tea towel and set aside in a warm place for a further 1 hour or until slightly risen.
• 8.
  Preheat the oven to 180°C.
• 9.
  Bake for 40-45 minutes until golden and cooked through (cover with foil if browning too quickly). Cool in the pan for 10 minutes, then turn out onto a wire rack.
• 10.
  Drizzle warm babka with melted chocolate to serve.