Cook polenta according to packet instructions, then pour onto a baking tray lined with greasproof paper and leave to cool, until the polenta becomes a solid block.
Heat the oil in a frying pan and transfer the polenta block to the pan. Fry on both sides until crisp and golden-brown.
Place the cream and the icing sugar in a clean bowl and whip together, until stiff peaks form when the whisk is removed.
To serve, place the warm polenta cake onto a clean plate. Sprinkle the cinnamon on top, add the whipped cream and garnish with the orange segments.