Delish - Flourless Orange & Almond Cake

Ingredients
2 large navel oranges
5 eggs
1 ¼ cups of caster sugar
2 ½ cups ground almonds
1 tspn gluten-free baking powder
Pure icing sugar (to serve)

Recipe
Preheat the oven to 170c. Grease and line the base of the pan.
Place the two whole oranges in a saucepan and cover with water. Bring to the boil and simmer, covered, for 1 hour, ensuring that the oranges remain covered with water. Drain and cool.
Chop the oranges into quarters, discard any seeds, then place the chunks into a blender and puree until smooth.
Beat the eggs and sugar until thick, then add the orange puree, ground almonds and baking powder. Mix well.
Pour into your prepared pan and bake for 1 hour. Leave the cake to firm up in the pan for 20mins, then turn out, remove the baking paper and turn over to finish cooling right away. This cake definitely mellows with a little time and can be prepared 48hrs in advance.
Sift icing sugar on top and decorate with orange zest and almonds.