Preheat the oven to 200C/400F/Gas 6.
Cut a 6in triangle out of the ready-rolled puff pastry. Place onto a baking sheet and sprinkle with the cinnamon and half a tablespoon of the caster sugar. Place into the oven to cook for ten minutes.
Place the cream, orange juice, icing sugar and vanilla seeds into a bowl, and whisk until the mixture forms soft peaks when the whisk is removed.
Place the orange segments onto a baking sheet, sprinkle with the rest of the sugar and using a mini-blow torch,caramalise the sugar for two minutes, or until golden.
To serve, place the oranges onto a serving plate, place some cream on top and then the cooked cinnamon pastry.