Preheat the oven to 350°F (175°C). Grease and flour two 9-inch round cake pans.
In a medium bowl, whisk together flour, baking powder, baking soda, and salt. Set aside.
In a large bowl, cream butter and sugar until light and fluffy.
Add eggs one at a time, beating well after each addition. Stir in lemon zest and juice.
Alternate adding the dry ingredients and buttermilk to the batter, beginning and ending with the dry ingredients. Mix in vanilla extract.
Divide the batter evenly between the prepared pans and bake for 25–30 minutes, or until a toothpick inserted in the center comes out clean.
Cool the cakes in pans for 10 minutes, then transfer to a wire rack to cool completely.