01 - Preheat oven to 350°F. Line two baking sheets with parchment paper.
02 - In a medium bowl, whisk together flour, baking soda, and salt. Set aside.
03 - In a large bowl, beat butter and sugar together until light and fluffy, about 2-3 minutes.
04 - Beat in lemon zest, egg, lemon juice, and vanilla extract until fully incorporated.
05 - Gradually add dry ingredients to wet mixture, mixing just until combined.
06 - Scoop tablespoon-sized balls of dough and roll each in extra sugar to coat.
07 - Place cookies 2 inches apart on prepared baking sheets.
08 - Bake for 9-11 minutes, until edges are lightly golden and centers are just set.
09 - Allow cookies to cool on sheet for 5 minutes before transferring to a wire rack to cool completely.