- Dissolve gelatin in water for 10 minutes. Lightly spray 8 ramekins with nonstick spray. Divide blueberries evenly into ramekins.
- In a medium-sized saucepan, heat cream with lemon zest and sugar over medium heat until sugar dissolves. Bring to a low boil, stirring to prevent scorching. Remove from heat.
- Stir in gelatin until well mixed. Cool to lukewarm. Stir in buttermilk and vanilla. Pour into the ramekins.
- Cover and chill until set, about 4 hours.
- To assemble, slide a knife around the edge of each chilled panna cotta and gently nudge out of ramekins. Spoon lemon curd over each serving and garnish with fresh blueberries.