Start the day before you want to bake the bread. Place the flour, yeast, salt, spices, sugar, pumpkin puree and egg in the bowl of a stand mixer fitted with a dough hook. Mix on a low speed until it comes together into a dough. Continue to mix for about 5 minutes at a high speed then add the butter a little at a time until it is all incorporated. Continue to mix at a high speed until the dough is smooth, elastic and comes away from the sides of the bowl cleanly. If it seems really too sticky then add a little more flour.
Place the dough in a lightly oiled bowl, cover with clingfilm and refrigerate overnight (or for up to 24 hours).
The following day, remove the dough from the fridge and turn out onto a floured surface, sprinkle with a little more flour then roll out to an approx 25x35cm rectangle. mix together the chocolate spread and the ground ginger then spread it evenly over the dough. Scatter over the chopped crystallised ginger.
Roll the dough up from one of the long edges into a log. Slice the log in half lengthways, exposing the filling. Twist the two halves together then shape into a circle, pinching the ends together to seal. Transfer onto a baking sheet lined with baking parchment, loosely cover with oiled clingfilm and set aside to rise for about an hour until the dough is puffy and springs back slowly when you press it with a finger.
Meanwhile, preheat the oven to 180C/350F/gas mark 4. Bake the bread for about 45 minutes until well risen, golden and cooked through - the internal temperature should reach at least 94C/202F. Cover loosely with tin foil partway through baking if the top starts to colour too much.
Leave the bread to cool on the tray before serving.