Place the ginger cardamom orange zest, raisins, and sugar into a mixing bowl and pour over the hot tea. Cover and leave to soak overnight.

The next morning, preheat the oven to 160C /325F/ gas mark 3. Add the beaten egg to the fruit mixture, followed by the flour, and mix well. Add the chocolate and mix again. Pour the mixture into a 1kg tin lined with baking parchment, and bake for 11/2 hours.

Allow the cake to cool in the tin for 30 minutes, then carefully remove. Wrap the cake in fresh parchment paper and a tea-towel for 24 hours before eating.

Serve with soft butter and a real hot chocolate.