Preheat the oven to 400°F. Place the frozen puff pastry shells top side up on an ungreased baking sheet about 2 inches apart. Bake for 20 to 25 minutes until puffed and deeply golden brown.
Let cool for a few minutes then gently remove the lid and soft inner pastry with a fork to create a cavity. Let cool completely before filling.
Add the cold heavy cream, powdered sugar, vanilla, and Koyah lemon powder to a chilled mixing bowl. Whip on medium-high with a hand mixer or stand mixer until medium-stiff peaks form — the cream holds its shape but still looks soft and billowy. Taste and adjust the sweetness or lemon flavor.
Spoon about 1 to 1 1/2 teaspoons of lemon curd into the bottom of each cooled shell.
Pipe or spoon a generous swirl of lemon whipped cream over the curd, filling each shell to the top.
Top with fresh blueberries and finish with a light sprinkle of lemon zest. Serve immediately.