DIRECTIONS TO MAKE THE GANACHE
1. Sprinkle the gelatin over the cold water in a small bowl. Let set for 10 minutes, until the gelatin softens.
2. Put the chocolate into a medium bowl and set aside.
3. Heat the crème fraîche, heavy cream, passion fruit puree, and corn syrup in a small saucepan until it just boils. Remove from the heat and stir in the gelatin until completely dissolved. Pour the cream over the chocolate and let sit for 1 minute.
4. Using a small rubber spatula, begin stirring the white chocolate mixture in one direction, concentrating on the center, until smooth and glistening. Add the butter and stir until it is completely melted, about 1 minute. Add the rose petals and stir until evenly distributed.
5. Put the ganache in the coolest part of your kitchen and let set, stirring occasionally, until spreadable, for about 1 hour before using.