For the currant jelly, place the currants in a large strainer and rinse with cold water. Drain well, then grate the berries from the stems and place in a large bowl. Sprinkle with sugar and let steep for at least 1 hour. Place a sieve in a saucepan and empty the berries into it.
Bring the currant juice, which will drain into the pot, to a boil with 500 ml water, vanilla sugar and cinnamon stick.
Soak the gelatine in cold water. Add currants to the boiling currant-sugar juice and bring to a boil again. Remove from heat.
Squeeze gelatin well and mix into currant mixture. Cool in a bain-marie, stirring frequently during this time.
As soon as the mixture becomes somewhat firm, place in a baking dish or tart pan (rinse with cold water beforehand) and allow to set in the refrigerator for at least 1 hour.
Turn the currant jelly out onto a plate and garnish with whipped cream and almond flakes.