Preheat oven to 350 and line a cupcake tin with liners.
In the bowl of a stand mixer with the paddle attachment, beat the butter and sugar until light and fluffy. Add in the eggs one at a time beating well after each addition. Remember to scrape down the sides of the bowl afterwards. Slowly add in the milk and vanilla.
Slowly add in the dry ingredients and mix until combined. Add in the lemon zest and lemon juice.
Fill the liners 3/4 of the way full and bake for 10-12 minutes or until a toothpick inserted comes out clean.