Soak the gelatin in a bowl with cold water for at least 5 minutes.
Put the cranberry juice, the double cream and the sugar together in a saucepan. Put on the heat and warm until the sugar is dissolved and hot enough to melt the gelatin but not boiling. Squeeze the moisture out of the gelatin and add to the cream mixture. Stir until dissolved.
Add the yogurt and the vanilla in and stir everything through.
Pour into the pannacotta tins, cover with cling film and put into the fridge for at least 4 hours but preferably overnight.
If you want to remove the pannacotta from the tins, fill a large bowl with warm water and gently dip the tin into the hot water until you can see the sides coming loose a little bit. Put a plate on top of the tin, turn around, holding both with your hands and it should come straight out.
Scoop the pomegranate seeds on top of the pannacotta and serve.