Bring a pot of water to the boil and immerse the oranges into it. Boil for 40-50 minutes until a knife inserted yields without any resistance. Remove and cool. Cut into half and get all the pips out; retain the outer skin and pulp. Add the orange to a blender and purée with the sugar until smooth.
Preheat oven to 180 C / 360 F and line a 8” spring-form pan with baking parchment.
In another bowl, add the rest of the ingredients - eggs, salt, baking powder and ground almonds and mix well with a spatula. Tip the orange purée into this and mix again until well incorporated.
Pour the batter into the pan and bake for 50 - 60 minutes. If the top of the cake starts to brown too quickly, cover with foil after 35 - 40 minutes and continue cooking. * Insert a skewer into the center of the cake once you think it’s done, to ensure that it’s fully cooked through - it should come out clean.
Place the pan on a wire rack and cool completely before unmoulding. Dust with icing sugar and serve.
Notes
* Adapted from Nigella Lawson
Recipe by The Blurry Lime at https://www.theblurrylime.com/cakes/orange-and-almond-cake/