Preheat oven to 400°F.
Unfold the puff pastry and cut into hearts using heart-shaped cookie cutters.
Place the puff pastry hearts on a baking sheet and bake for 10-12 minutes, or until golden brown.
In the bowl of a standing mixer, or with an electric mixer whip the cream on medium- high speed for 2-3 minutes. Add the powdered sugar and beat on high for 30 more seconds or until thick and fluffy.
Remove hearts from the oven and allow to cool completely. Slice hearts in half. Top the bottom half with whipped cream and berries, and place the other half on top to form a sandwich.