Preheat oven to 350°F. Grease 2 8-inch cake pans with butter and flour.
Whisk together flour, baking powder, baking soda, salt, and cream of tartar.
Using the paddle on a stand mixer, cream the butter and sugar together on high speed (about 3 minutes).
Add in eggs and vanilla extract on high speed until light and creamy (about 3-5 minutes).
On low speeds, slowly add in the dry ingredient until the mixture is just combined.
With the mixer running on low speeds, add in milk, lemon juice, and lemon zest until batter is smooth.
Pour batter evenly into the cake pans.
Bake for 35 to 40 minutes or until a toothpick can cleanly come out of the center of the cake.
Give cakes 5 to 10 minutes to cook before removing them from the pans.
The cake should be completely cooled before assembling and decorating as desired.
Enjoy!!