Place clementines in a saucepan with water.
Boil for two hours until very soft.
Let them cool completely before processing.
Preheat your oven to 375°F (190°C).
Grease and line the cake pan well.
Cut cooled clementines and remove any seeds.
Blend clementines into a smooth puree.
Beat eggs and sugar until light.
Fold in ground almonds and baking powder.
Add clementine puree and mix gently.
Pour batter into the prepared pan.
Bake for 60 minutes until golden.
Test with a skewer for doneness.
Cool in pan for 15 minutes.
Transfer to a wire rack completely.