Preheat the oven to 350°F (175°C).
In a mixing bowl, beat together butter and sugar until light and fluffy.
Add lemon zest, lemon juice, and egg, mixing to combine.
Gradually mix in the flour, baking soda, and salt.
Cover the dough with plastic wrap and refrigerate for 30-60 minutes.
Roll the chilled dough into balls, then roll each ball in sugar.
Place the dough balls on a lined baking sheet, spacing them 2 inches apart.
Bake for 11-13 minutes or until edges are lightly golden.
Cool on the baking sheet for 5 minutes before transferring to a wire rack.