Wash the strawberries with their stems; dry them on a tea towel and remove the stems, except for a few to be used for garnishing. Put the sheets of gelatin in a bowl of cold water to soak. Pour the cream into a heavy-bottomed saucepan. Cut the vanilla pod open lengthwise, scrape out the seeds and put them into the cream together with the pod itself. Now add the sugar, stir and bring the cream to the boil over a very low heat, stirring continuously. Take the pan off the stove, cover and allow to rest for 5 minutes. Remove the vanilla pod. Take the sheet gelatin out of the water and squeeze it well with your hands. Then put it in a small saucepan over a heat that’s so low you can stir it with your index finger, at “finger temperature” (it will only take a few seconds). Add the dissolved gelatin to the hot (but not boiling) cream, stirring well. Pour half of this mixture into a rectangular mould, such as a loaf tin, and put it in the fridge. As soon as it has set, cover the surface with the strawberries (either whole or cut in half, depending on their size). Now pour in the other half of the cream, which you have left at room temperature, and put the mould back in the fridge for 4-5 hours.
After this time (but you can also prepare it the day before you want to use it) upturn the mould on an oval or rectangular serving dish. To make it easier to get the panna cotta out, delicately slide a thin spatula, previously dipped in cold water, all around the sides. Garnish it with the strawberries you set aside and, if you like, with 2 or 3 spoonfuls of “Fragolina” strawberry purée drizzled on top.
You can serve this special panna cotta with a strawberry sauce or with strawberry ice cream and biscuits.