Put the whole oranges in a pan and cover with cold water. Bring to the boil, turn down the heat and simmer for up to two hours. Check the water to ensure they don't boil dry. After two hours, remove from the heat and leave to cool.
Preheat the oven to 200C/400F/Gas 6.
Remove the oranges from the water. Cut in half and remove the pips.
Place them in a food processor, skin and all, with all of the remaining ingredients and blend until mixed.
Put the mixture into a greased and lined cake tin (20cm/8in) and bake for 45 minutes.
Let the cake cool before serving with a dollop of crème fraîche and a scattering of raspberries.
