Step 1: In a large bowl, cream together the softened butter, 1/2 cup powdered sugar, and vanilla extract with an electric mixer until light and fluffy.
Step 2: Beat in the fresh lemon juice and lemon zest until well combined.
Step 3: In a separate bowl, whisk together the all-purpose flour and salt. Gradually add the dry ingredients to the wet ingredients, mixing on low speed until just combined and a soft dough forms. Do not overmix.
Step 4: Cover the bowl with plastic wrap and chill the dough in the refrigerator for at least 30 minutes.
Step 5: Preheat your oven to 350°F (175°C). Line baking sheets with parchment paper.
Step 6: Roll the chilled dough into 1-inch balls and place them about 1 inch apart on the prepared baking sheets.
Step 7: Bake for 10-12 minutes, or until the edges are very lightly golden. The cookies should still be pale.
Step 8: While the cookies are still warm (but cool enough to handle), roll them generously in extra powdered sugar. Let them cool completely on a wire rack.
Step 9: Once cooled, roll them in powdered sugar a second time for a thicker, 'snowier' coating, if desired. Serve and enjoy!