Preheat the oven to 350°F.
In a large mixing bowl, cream the softened butter and sugar together until fluffy.
Beat in the eggs, lemon juice, and lemon zest until everything is well combined.
Gradually stir in the flour, baking powder, and salt until the dough comes together nicely.
Roll the dough into tablespoon-sized balls and place them on lightly greased cookie sheets. For a fun touch, flatten each ball with a glass dipped in sugar.
Bake the cookies for 9-10 minutes, or until they are just barely light brown on the bottom.
Allow them to sit for 3-4 minutes on the pan, then carefully remove them to a cooling rack.
Once the cookies are cool, it’s time to frost them! To make the frosting, beat together the softened butter, powdered sugar, salt, lemon zest, and lemon juice until the mixture is creamy. You can add milk if needed to reach your desired consistency.