Lavender Shortbread Cookies

• 1 cup butter (2 sticks), softened
• 1/4 cup granulated sugar, plus extra for sprinkling on cookies
• 1/4 cup powdered sugar
• 1/4 teaspoon salt
• 1 cup all-purpose flour
• 1 cup cake flour
• 1 tablespoon chopped fresh lavender

In a stand mixer fitted with a paddle attachment, cream the butter, granulated sugar, powdered sugar, and salt until thoroughly combined, about 3 minutes. In a separate bowl, sift together the all-purpose and cake flours. Mix the flour mixture into the butter mixture in 3 additions, scraping down the sides of the bowl in between each addition. Add the lavender and mix to just combine.

Roll out the dough to a 1/2-inch-thick rectangle. Wrap in plastic wrap and refrigerate for at least 4 hours.

Preheat the oven to 350ºF. Cut the dough into 2 x 1-inch bars and place on a parchment-lined baking sheet. Bake the cookies until just golden at the edges, about 20 minutes. Remove from the oven and immediately sprinkle with granulated sugar. Let cool completely before serving.