How to Make It
In a small bowl, sprinkle the gelatin evenly over 2 cups of the cranberry juice. Let stand until the gelatin has softened, about 5 minutes.
In a medium saucepan, bring the remaining 6 cups of cranberry juice to a simmer. Remove from the heat and stir in the honey and orange-flower water. Whisk in the gelatin mixture. Let cool for about 1 hour, stirring occasionally.
In a small bowl, sprinkle the gelatin evenly over the water and let stand until softened, about 5 minutes. In a large heatproof bowl, whisk 3 cups of the heavy cream with the yogurt.
In a medium saucepan, combine the remaining 3 cups of heavy cream with the sugar and the vanilla beans and seeds and bring to a simmer over moderately high heat, stirring often to dissolve the sugar. Remove the saucepan from the heat and whisk the gelatin mixture into the hot vanilla cream. Strain the cream through a fine-mesh sieve set over the yogurt mixture and whisk thoroughly to blend. Let yogurt panna cotta cool for about 45 minutes, stirring occasionally.
Set 20 small and sturdy plastic glasses on a tray. Ladle 1/4 cup of the yogurt panna cotta mixture into each glass (see Note) and refrigerate until set, about 3 hours.
Carefully ladle about 6 1/2 tablespoons of the cranberry jelly over the panna cotta layer and refrigerate until set, about 2 hours.
About 30 minutes before adding the last layer, gently warm the remaining panna cotta mixture just until melted. Ladle 1/4 cup of the panna cotta into each glass. Cover the glasses with plastic wrap and refrigerate until firm, about 2 hours longer. Serve chilled, garnished with small clusters of red currants.