01 -
Preheat your oven to 350°F / 180°C / gas mark 4. Line 2 baking sheets with parchment paper.
02 -
In a small bowl, whisk together the flour, cornstarch, and baking powder. Set aside.
03 -
Using a large mixing bowl and a stand mixer fitted with the paddle attachment (or an electric mixer), cream the butter, sugar, lemon zest, and lavender on medium speed until light and fluffy, about 2 to 3 minutes. Scrape down the sides of the bowl.
04 -
Mix in the egg until very well combined, ensuring it's fully incorporated into the butter mixture.
05 -
Using low speed, add the flour mixture and mix until just combined. The dough will seem slightly dry but should hold together when pressed.
06 -
Use a small cookie scoop to drop 1-tablespoon-sized balls of dough onto the prepared baking sheets. Space the dough balls 2 inches / 5 cm apart to allow room for spreading.
07 -
Gently flatten each ball with your palms until 1/3 inch / 1 cm thick to create even, round cookies.
08 -
Bake the cookies for 12 to 15 minutes, one sheet at a time. The cookies are ready when the center is just set and the edges appear slightly golden.
09 -
Cool the cookies on the baking sheet for 5 minutes. Then, transfer them onto a wire rack to cool completely before glazing.
10 -
In a medium bowl, whisk together the powdered sugar, lemon juice, and lavender extract (if using). The consistency should be thick but pourable. Add more lemon juice if too thick or more powdered sugar if too thin. Tint the glaze with a few drops of purple food coloring.
11 -
Spoon glaze over each cookie. If desired, while the glaze is still wet, sprinkle the cookies with additional lavender buds and lemon zest for garnish. Let the icing set for about 30 minutes before serving.