01 - In a large bowl, cream together softened butter and powdered sugar until light and fluffy using an electric mixer.
02 - Mix in fresh lemon juice, lemon zest, and vanilla extract until fully incorporated.
03 - Add salt, flour, and cornstarch. Mix on low speed until a soft, pliable dough forms.
04 - Divide dough in half and roll each portion into a 1-inch diameter log. Wrap tightly in plastic wrap and refrigerate for at least 30 minutes until firm.
05 - Preheat oven to 350°F. Line two baking sheets with parchment paper.
06 - Unwrap chilled dough and slice into 1/4-inch rounds. Arrange on prepared baking sheets, leaving 1 inch of space between cookies.
07 - Bake for 10-12 minutes until edges are just barely golden. Avoid overbaking to maintain tender texture.
08 - Remove from oven and let cookies rest on baking sheets for 5 minutes. While still warm, gently toss in powdered sugar to coat evenly.
09 - Transfer cookies to a wire rack to cool completely. Dust with additional powdered sugar before serving for extra presentation.