01 -
Preheat the oven to 350°F (177°C). Line a 12-cup muffin pan with cupcake liners. This recipe yields about 15 cupcakes, so prepare for a second batch.
02 -
Whisk the flour, baking powder, and salt together in a large bowl. Set aside.
03 -
Using a handheld or stand mixer fitted with a paddle attachment, beat the butter, sugar, and lemon zest on medium-high speed in a large bowl until creamy, about 2 minutes. Scrape down the sides of the bowl as needed.
04 -
Add eggs and vanilla extract. Beat on medium-high speed until combined, about 1 minute. Scrape down the sides of the bowl as needed.
05 -
On low mixer speed, gradually add the dry ingredients while streaming in the milk and lemon juice. Beat until just combined. Gently fold in the floured blueberries. Avoid overmixing.
06 -
Pour or spoon the batter into the liners, filling only two-thirds full to prevent overflow.
07 -
Bake for 18–21 minutes, or until a toothpick inserted in the center comes out clean. For mini cupcakes, bake for 11–13 minutes at the same temperature. Cool the cupcakes completely before frosting.
08 -
In a large bowl, using a handheld or stand mixer fitted with a whisk or paddle attachment, beat the cream cheese and butter together on medium speed until smooth, about 2 minutes. Add confectioners' sugar, vanilla, and salt. Beat on low speed for 30 seconds, then at medium-high speed for 2 minutes until fully combined. Chill frosting for 20 minutes if piping intricate designs.
09 -
Frost cooled cupcakes using a piping bag or spatula. Garnish with optional lemon slices or blueberries, if desired.
10 -
Refrigerate decorated cupcakes uncovered for at least 20 minutes before serving to set the frosting. Store leftovers covered in the refrigerator for up to 5 days.