01 - Preheat oven to 350°F. Grease and flour two 8-inch round cake pans and line bottoms with parchment paper.
02 - Whisk together flour, baking powder, baking soda, and salt in a medium bowl.
03 - Beat butter and sugar in a large bowl until light and fluffy, about 3 minutes.
04 - Add eggs one at a time, mixing well after each addition. Stir in lemon zest, lemon juice, and vanilla extract.
05 - Add dry ingredients in three parts, alternating with milk, beginning and ending with dry ingredients. Mix until just combined.
06 - Toss blueberries with 1 tablespoon flour, then gently fold into batter.
07 - Evenly divide batter between the prepared pans.
08 - Bake for 30 to 35 minutes, or until a toothpick inserted into the center comes out clean.
09 - Cool cakes in pans for 10 minutes, then transfer to wire racks to cool completely.
10 - Beat cream cheese and butter until smooth. Gradually add powdered sugar, lemon zest, lemon juice, vanilla extract, and salt. Beat until light and fluffy.
11 - Place one cake layer on serving plate; spread with frosting. Top with second layer and frost top and sides.
12 - Decorate with fresh blueberries and additional lemon zest if desired.