Prepare the pastry
Unroll the puff pastry and prick it all over with a fork to prevent excessive puffing. Cut the pastry into 12 squares and place them in tartlet molds.

Fill & Bake
Brush the surface of the pastry with the beaten egg and add 3 teaspoons of lemon curd to each mold.
Bake in a preheated oven at 170°C (340°F) for about 25 minutes, until golden and crisp.

Whipped cream topping
While the tartlets are baking, whip the heavy cream with 4 tablespoons of powdered sugar, the lemon zest, and vanilla extract until it forms a light, fluffy whipped cream.

Serving
Once the tartlets have cooled, dust them with the remaining powdered sugar, pipe the whipped cream on top, and finish with a fresh mint leaf for garnish.