Nigella's gorgeous gluten-free chocolate orange cake is smothered in a rich chocolate ganache and decorated with mouthwatering chocolate orange segments. (Recipe from Feast by Nigella Lawson. Chocolate Orange Glaze recipe adapted from Martha Stewart.)
Put the oranges in a saucepan with cold water and bring to the boil before reducing the heat and simmering for 2 hours, or until soft. Drain the water and set aside to cool. When cool, cut the oranges in half and remove any large pips.
Grease an 8" (20 cm) springform pan and preheat the oven to 350 degrees Fahrenheit (80 Celsius).
Pulp the orange in a food processor before adding the eggs, baking powder, bicarbonate of soda, almonds, sugar and cocoa and processing until you have a smooth batter- but still flecked with orange.
Pour the batter into the springform pan and bake for 1 hour. Check the cake after 45 minutes as you may need to cover it with foil to prevent burning before the cake is cooked through.
Let the cake cool in the tin before removing.
For the glaze, chop the chocolate into small pieces and place into a bowl. Pour the cream into a saucepan and heat until almost boiling and then pour over the chocolate pieces. Let it stand for 5 minutes before stirring until smooth. Let it stand for 10 minutes before decorating the cake with the optional chocolate orange slices.