In a pot over medium heat, gently heat the cream, milk, sugar and vanilla seeds, stirring constantly, until the sugar has dissolved. Remove from the heat.
Add the gelatin and whisk until completely dissolved.
Pour the mixture into twelve 1-cup (250 ml) jars. Cover and refrigerate for 6 hours or until the panna cotta has set.
Raspberry and Cranberry Jelly
Meanwhile, in a bowl, sprinkle the gelatin over the water. Let bloom for 5 minutes.
In a pot, bring the raspberries, cranberries, sugar and lemon juice to a boil while stirring frequently. Simmer for 5 minutes or until the mixture has thickened and the cranberries have burst.
In a blender, purée the mixture until smooth. In a sieve set over a bowl, strain the fruit mixture. Discard the seeds.
Add the gelatin to the fruit mixture and stir until completely dissolved. Reheat in the microwave oven if the mixture is not warm enough to dissolve the gelatin. Cover and refrigerate until completely chilled, about 2 hours.
Pistachio Praline
In a small pot over high heat, cook all of the ingredients, stirring with a wooden spoon, until the sugar crystalizes around the pistachios, about 3 to 4 minutes. Immediately spread out on a plate.
Assembly
In a bowl, whisk the mascarpone, sugar and vanilla seeds with an electric mixer until the sugar has dissolved. With the machine running on low speed, gradually add the cream. Increase the speed of the mixer and beat until firm peaks form. Transfer the mascarpone cream to a pastry bag fitted with a star tip.
Carefully top the panna cotta with the raspberry and cranberry jelly. Layer in the biscotti and mascarpone cream. Top with the pistachio praline.
Note from Ricardo
The panna cotta, raspberry and cranberry jelly, and pistachio praline can be prepared up to 3 days in advance. In this case, assemble the dessert just before serving.
