Whisk together the blood orange juice, water, and gelatin in a small bowl and set aside. Bring the sugar and heavy cream to a boil in a small pot over medium heat, whisking every couple minutes. Once it begins to boil, lower the heat to a simmer and whisk in the gelatin mixture. Continue cooking for two minutes, whisking the entire time. Remove from heat and whisk in the blood orange zest and the vanilla extract until combined. Allow the mixture to cool to room temperature before distributing into 6 separate ramekins. Place the ramekins in the refrigerator to gel for 6 hours or overnight. Once set, drizzle a bit of the syrup from the candied blood oranges into each ramekin (a tablespoon or two depending on how sweet you want it) and garnish each ramekin with a candied blood orange. Serve immediately.