Puree the strawberries until very smooth.
Push the puree through a sieve to remove seeds, or skim them off the top using a spoon. 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 strawberry 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.
Run knife around edges of ramekins, and invert onto serving plates.
Slice the remaining 8 strawberries into fans.
Top with whipped cream and sliced strawberries, if desired.