Place the gelatine in a bowl of cold water and allow to soak for about 5 minutes.
Pour the cream, vanilla, sugar and tea leaves in a saucepan. Simmer (don't boil!) over low heat for five minutes.
Pour the tea cream through a fine-meshed sieve into a bowl to separate out the tea leaves.
Remove the gelatine from its saucepan and squeeze well to remove as much water as possible. Add to the hot tea cream and stir to dissolve.
Pour into 4 cold jars or forms. Allow to cool to room temperature before refrigerating for 3-4 hours before serving. If time is of the essence, place the bowl in an ice bath and stir the mix until cool then pour into the forms.
To serve: If in jars, top with raspberries and dust with icing sugar.
To remove the panna cotta from the forms, hold the forms in warm water for a few seconds before tipping upside down onto a plate. Surround with some raspberries dusted with icing sugar.
If you have another type of black tea that you prefer, by all means, use that instead.If you only have tea bags on hand, remove the tea from the bag to use.Even as it cools, the panna cotta will be quite runny. It will only start to thicken once it has been in the refrigerator for about an hour, but it may require longer to set all the way through.When you refrigerate, cover the panna cotta, if possible, so that they do not develop a strange taste from an odour in the fridge.