In a very small saucepan sprinkle gelatin over water and let stand about 1 minute to soften. Heat gelatin mixture over low heat until gelatin is dissolved and remove pan from heat.
In a large saucepan bring cream, half-and-half, and sugar just to a boil over moderately high heat, stirring. Remove pan from heat and stir in gelatin mixture and vanilla. Divide cream mixture among 8 heart shaped ramekins and cool to room temperature. Chill ramekins, covered, at least 4 hours or overnight.