Preheat the oven to 400° F. Line muffin tins with 15-18 cupcake liners (mine made 18).
Whisk together flour, baking powder, and baking soda. Set aside.
In a stand mixer, beat the butter on low until it's soft. Then add the sugar and beat until fluffy for about 4 minutes.
Add eggs one at a time, beating until mixed after each egg.
Add the lemon juice and zest and beat until mixed. The mixture will look curdled.
Add the flour in three additions, alternating with the buttermilk, beginning and ending with the flour. Scrape the bowl, then mix on low until just combined.
Fill each cupcake liner ⅔ full. Bake for 13-16 minutes and check for doneness by inserting a toothpick into the center and it comes out clean. Allow them to cool completely before frosting.