This recipe is from Chef Adam Ross at Le Fanfare in Greenpoint, Brooklyn, NY.
1 lb. Concord Grapes
1 pint Heavy Cream
5 oz. Sugar
1/2 Vanilla Bean
3 sheets of Leaf Gelatin or 1 Envelope of Powdered Gelatin
Rinse grapes and remove stems. Process very briefly in a food processor, blender or mortar and pestle, just to crush the grapes but without grinding the seeds.
Combine grapes, cream and sugar in a saucepan. Split vanilla bean with a knife, scrape seeds from both sides, and add pod and seeds to the cream. Bring to a boil over medium heat, watching so it doesn't boil over. When cream boils, cover with a lid and remove from heat. Leave it to infuse for at least 20 minutes.
If using leaf gelatin, soak the sheets in a bowl of cold water until soft, then remove them, squeeze water out, and place gelatin in a large pitcher. If using powdered gelatin, sprinkle over a small bowl of about 1/4 cup of cold milk to bloom, stir well to make sure all the gelatin is dissolved, then transfer to a large pitcher. Return cream to a boil and then pass through a fine strainer into the container with the soft gelatin.
Stir well and pour into ramekins or cups. Refrigerate overnight to set. Serve the next day, garnished with whipped cream and chopped toasted hazelnuts.