In a medium bowl, whisk flour, baking powder, baking soda, and salt together. Set aside.
In a large mixing bowl, beat butter until creamy. Add sugar, lemon juice, and lemon zest, and beat until combined.
Add eggs, one at a time, and beat until combined.
Next, add flour mixture, alternating with buttermilk, and mix on low speed after each addition until combined.
Pour cake batter evenly into prepared cake pans.
Bake for 35-40 minutes or until a toothpick inserted in the center comes out clean.
Cool on a wire rack and remove from the pans after 10 minutes. Cool cakes completely before frosting.