In a mixing bowl, combine the sifted flour and powdered sugar. This ensures a light and tender crust.

Add the cold, cubed butter to the flour mixture. Using a pastry cutter or your fingers, mix until the mixture resembles coarse crumbs.

In a small bowl, whisk together the egg yolk and cold water. Add this to the flour mixture and mix until the dough just comes together.

Form the dough into a disk, wrap it in plastic wrap, and refrigerate for at least 30 minutes. Chilling the dough helps prevent shrinkage during baking.

Preheat your oven to 350°F (175°C). This ensures even baking.

On a lightly floured surface, roll out the chilled dough to about 1/8 inch thick. Use a round cutter to cut out circles that fit your mini tartlet pans.

Press the dough circles into the tartlet pans and trim any excess. Prick the bottoms with a fork to prevent bubbling.

Bake the crusts in the preheated oven for 12-15 minutes or until lightly golden. Allow them to cool completely before filling.

In a saucepan, combine the lemon juice and crushed lavender. Heat over low heat until warm (not boiling) to infuse the lavender flavor.

In a mixing bowl, whisk together the granulated sugar and eggs until pale and fluffy. This aerates the mixture for a light filling.

Remove the saucepan from heat and strain the lemon-lavender mixture through a sieve to remove the lavender bits.

Add the strained lemon juice to the egg mixture, along with the heavy cream, vanilla extract, and salt. Whisk until smooth.

Pour the lemon-lavender filling into the cooled tartlet shells, filling them about 3/4 full.

Bake in the oven for an additional 10-12 minutes, or until the filling is set but still slightly jiggly in the center.

Remove from the oven and let cool completely on a wire rack. This cooling step is crucial for the filling to firm up.

Once cooled, dust the tartlets with powdered sugar and garnish with fresh lavender sprigs for a beautiful presentation.

Serve chilled or at room temperature. Enjoy the refreshing flavors of lemon and lavender!