Preparation
Preheat oven to 180°C (160°C fan, gas 4). Line a baking tray with baking paper.
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Grate the zest from the oranges.
Blitz with the almonds in the blender.
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Melt the butter in a pan then allow to cool.
Whisk the eggs with the sugars and salt until frothy.
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In a second bowl, mix the flour, baking powder and orange-almond mix. Stir in the egg mixture and the cooled butter.
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Pour or spoon into the prepared springform tin and spread level.
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Bake in the oven for 50 minutes until golden brown and a skewer inserted into the centre comes out clean. Remove from the oven, cool slightly, carefully turn out onto a wire rack and leave to cool. Remove the baking paper.
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Peel the oranges, cutting off all the white pith.
Cut out the blood orange segments.
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Halve the sponge horizontally, spread with the bottom layer with lemon curd and place the other layer on top. Dust with icing sugar and serve with orange segments.
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