Place the oranges into a small saucepan, half filled with water and place on medium heat, covering.
Simmer for 1 ½ - 2 hours, adding more water to the saucepan as needed, until very soft.
Preheat the oven to 170C/340F and line a cake tin with greaseproof paper.
Remove from the heat and allow to cool completely.
Slice and remove any pips.
Toss into a blender and puree until finely chopped.
Pour the oranges into a medium bowl and set aside.
Add the eggs, ground almonds, sugar and baking powder into the blender and mix until fine.
Pour the almond mixture into the oranges and stir together until your batter is combined.
Pour into your cake tin and smooth out.
Bake for 55 minutes or until lightly golden and a skewer comes out clean, when inserted.
Remove and allow to cool completely.
Serve with a dollop of whipped cream or yogurt and a cup of tea.
Enjoy!