Wash the navel oranges, cut off the ends (discard the ends) and place the oranges into a large pot.
Cover with water, bring to the boil on the stovetop, then simmer for 2 hours (add more water during this time).
Remove the oranges from the water and allow to cool completely (they'll be nice and soft).
Preheat oven to 160 degrees celsius (fan-forced). Grease and line the base and sides of a 22cm springform pan with baking paper and set aside.
Chop the cooled oranges into pieces and place into a food processor.
Process until completely smooth and no lumps remain. Set aside.
Beat the eggs and caster sugar in a large bowl until pale and frothy (about 2 minutes on high using hand-held beaters).
Add the orange puree and stir through.
Add the almond meal and baking powder and stir through.
Pour the mixture into the prepared baking tin.
Sprinkle the flaked almonds over the top of the cake.
Bake for 60 minutes or until a skewer inserted into the middle comes out with just a few crumbs on it.
Allow to cool completely in the tin (preferably overnight) and store at room temperature.
Dust with icing sugar just before serving.
Thermomix Method
Wash the navel oranges, cut off the ends (discard the ends) and place the oranges into a large pot.
Cover with water, bring to the boil on the stovetop, then simmer for 2 hours (add more water during this time).
Remove the oranges from the water and allow to cool completely (they'll be nice and soft).
Preheat oven to 160 degrees celsius (fan-forced). Grease and line the base and sides of a 22cm springform pan with baking paper and set aside.
Chop the cooled oranges into pieces and place into the TM bowl. Slowly increase to Speed 7 and continue to process until completely smooth (you'll need to scrape down the sides of the bowl occasionally). Set aside in a separate bowl.
Clean and dry the TM bowl. Add the eggs and caster sugar and mix for 30 seconds on Speed 5.
Add the orange puree and mix for 10 seconds on Speed 5.
Add the almond meal and baking powder and mix for 20 seconds on Reverse, Speed 3.
Pour the mixture into the prepared baking tin.
Sprinkle the flaked almonds over the top of the cake.
Bake for 60 minutes or until a skewer inserted into the middle comes out with just a few crumbs on it.
Allow to cool completely in the tin (preferably overnight) and store at room temperature.
Dust with icing sugar just before serving.
Notes
RECIPE NOTES
Whole orange cake recipe - this cake is made using whole oranges (including the peel!) The oranges are boiled until soft and then pureed into a smooth paste.
Boiling time - boil the oranges for 2 hours before chopping into pieces and pureeing until smooth.
Make the puree ahead of time - you can boil the oranges and prepare the puree ahead of time. Store in the fridge in an airtight container for up to 3 days. Alternatively, freeze for up to 2 months. Allow to defrost before using. You can also make a double batch of the orange puree so you have extra sitting in the freezer ready to go!
Almond meal - you can buy packets of pre-made almond meal from the nuts section of any supermarket. Almond meal is the same as ground almonds – so you can always make your own almond meal by grounding whole almonds if you prefer.
Springform tin - I recommend using a greased and lined springform tin. This allows the dense cake to be easily removed after baking and doesn’t disturb the flaked almonds on top. However, if you don’t have a springform tin, you can use a well greased and lined cake tin (with the base and sides lined with baking paper) and very carefully remove the cake once it’s cooled.
Browning on top - if you notice that your cake is browning too much, simply place a sheet of foil loosely over the top and continue to cook.
Storing and serving - this cake can be kept in an airtight container at room temperature for up to 4 days or frozen for up to 2 months. Dust with a little icing sugar and serve at room temperature or warmed up slightly.
Serving suggestings - a dollop of thick cream, a scoop of ice cream or drizzle with custard, even a drizzle of berry coulis for extra luxe!