1cup(226 g or 2 sticks) unsalted butter, room temperature
2 ½cups(300 g) confectioners’ sugar, sifted
2Tablespoonsfresh lemon juice
Preheat the oven to 350 F. Line a standard 12-cup muffin tin with paper liners and set aside.
In a medium bowl, whisk together flour, baking powder, baking soda and salt. Set aside.
In the bowl of a stand mixer (or using a hand mixer), combine sugar and lemon zest. Rub the lemon zest into the sugar to increase its flavor. Add butter and use an electric mixer to beat on medium-high speed until light and fluffy, about 2 minutes. Add eggs and mix until combined. Add lemon juice and mix again (it's okay if the batter looks slightly curdled at the point).
Add half the flour mixture to the wet ingredients and mix just until combined. Add the milk and mix until combined. Add remaining flour mixture and mix just until combined. Scrape down the sides and bottom of the bowl as necessary.
Use an ice cream scoop to transfer batter to prepared pan, filling each cup about ¾ full. Bake cupcakes at 350 F for 20 to 22 minutes or until a toothpick inserted in the center comes out with little to no crumbs. Allow cupcakes to cool in pan for 5 minutes before transferring to a wire rack to cool completely.
To make the lemon buttercream frosting, beat butter on medium-high speed with an electric mixer until light and fluffy. Add confectioners’ sugar and mix until combined (it may look dry at first, but it will come together). Add lemon juice and mix until smooth. If a thinner consistency is required, add milk one tablespoon at a time.
Transfer frosting to a piping bag with desired tip and frost cupcakes. Garnish with lemon zest and serve.
Lemon juice: Use fresh lemon juice for the best flavor. Store-bought lemon juice does not provide nearly enough flavor.Store lemon cupcakes in an airtight container at room temperature for up to 3 days or in the refrigerator for 5 days.Can you freeze lemon cupcakes? Yes. Let the cupcakes cool completely, then store in an airtight container or freezer bag for up to 1 month. Defrost in the refrigerator before bringing to room temperature and frosting.Recommended tools: Muffin tin, kitchen scale, hand mixer or stand mixer, ice cream scoop, frosting bag and tips