1. In a saucepan, combine the cream, 1/2 cup of sugar, and the vanilla pods and seeds. Cook over low heat, stirring until the sugar is dissolved.2. Set aside half a cup of the mixture in a small bowl, sprinkle 1 1/2 teaspoons of gelatin powder on top, and place it over a saucepan of simmering water. Stir until the gelatin is dissolved. Add it to the mixture. Let it cool slightly and whip in the yogurt.3. Pour into 4 glass bowls, leaving space at the top, and refrigerate for 2 hours.4. In a saucepan, combine the passion fruit juice and the remaining sugar, and sprinkle the remaining gelatin powder on top. Cook over low heat, stirring gently, until the gelatin is dissolved. Cool, then filter. Pour over the panna cotta (it’s okay if there are a few seeds in the jelly).5. Refrigerate for 2 hours or until set. Serve with shortbread cookies.