Preheat your oven to the temperature recommended on the puff pastry package instructions. Line a baking sheet with parchment paper.
Follow the package directions to thaw the puff pastry. Once thawed, unfold the sheet and cut it into small squares or rectangles, about 2x2 inches in size.
Place the cut puff pastry pieces onto the prepared baking sheet, leaving some space between each piece. Bake them in the preheated oven for the time specified on the package, or until golden brown and puffed up.
While the puff pastry is baking, prepare the lemon cream. In a mixing bowl, combine the heavy whipping cream and powdered sugar. Using an electric mixer or whisk, whip the cream until it forms stiff peaks.
Gently fold in the lemon juice and lemon zest into the whipped cream until well combined.
Transfer the lemon cream into a piping bag fitted with a star tip.
Once the puff pastry has cooled, slice each piece horizontally, creating a top and bottom layer.
Pipe a generous amount of lemon cream onto the bottom half of each puff pastry piece.
Place the top half of the puff pastry on the cream, gently pressing down to sandwich them together.
Repeat this process with the remaining puff pastry pieces.