Puree the blackberries until very smooth. Press the puree through a sieve to remove seeds. Set aside.
Pour the whole milk into a large saucepan.
Sprinkle with the gelatin and let sit until gelatin softens, about 5 minutes.
Turn the heat to medium, and cook, stirring until gelatin dissolves and until the mixture simmers.
Add the blackberry puree, heavy cream, sugar, and vanilla.
Cook, stirring, until sugar dissolves.
Divide among 8 ramekins coated with cooking spray.
Cover and refrigerate until set, about 3-4 hours.
Meanwhile, prepare orange curd.
When ready to serve, run knife around edges of ramekins, and invert onto serving plates.
Top with 1-2 tbsp. orange curd.