Flour mixture: In a small bowl, stir together flour and salt. Set aside.
Butter mixture: In a large mixing bowl, use an electric hand mixer to beat the softened butter until it becomes very creamy. Add the powdered sugar, lemon juice, and lemon zest. Beat on low speed until creamy and fluffy.
Combine flour and butter mixtures: Add the flour mixture and mix on low speed until it forms a crumbly dough. It may look a bit dry at first but it'll come together if you keep mixing. It should stick together if you squeeze a handful of dough together.
Press dough together: Turn the dough out onto a sheet of parchment paper. Use your hands to press the dough together into a flattened disc shape.
Roll dough: Lay another sheet of parchment paper on top of the dough. Use a rolling pin to roll the dough out until about ¼" thick.
Chill dough: Slide the parchment paper onto a cutting board to transfer it to the fridge. Chill the dough sheet in the fridge for about 1 hour or until firm.
Prep: Preheat the oven to 350°F. Line a baking sheet with parchment paper and set aside.
Cut out cookies: Once chilled, peel the top layer of parchment paper off the dough sheet. Use a 3" scalloped cookie cutter to cut out cookies from the dough. Place each cookie on your lined baking sheet, leaving about 1" in between each cookie. Re-roll the scraps and cut out more cookies. If the dough has become too soft while you've been working with it, chill the baking sheet in the fridge for about 15 minutes before baking.
Bake: Bake the cookies for about 14-15 minutes or until the bottom edges of the cookies begin to lightly brown.
Cool: Let the cookies cool on the baking sheet for about 5 minutes before transferring them to a wire rack to cool completely before icing.