Preheat Oven: Preheat the oven to 350°F (175°C). Grease and line three 8-inch round cake pans with parchment paper.

Prepare Dry Ingredients: In a medium bowl, whisk together the flour, baking powder, baking soda, and salt. Set aside.

Cream Butter and Sugar: In a large bowl, beat the butter, sugar, and lemon zest with an electric mixer until light and fluffy, about 2–3 minutes.

Add Eggs and Lemon Juice: Beat in the eggs, one at a time, until fully incorporated. Mix in the lemon juice and vanilla extract.

Combine Wet and Dry Ingredients: Gradually add the dry ingredients to the wet ingredients, alternating with buttermilk. Begin and end with the dry ingredients. Be careful not to overmix.

Fold in Blueberries: Gently fold in the floured blueberries, ensuring they are evenly distributed.

Bake the Cake: Divide the batter evenly among the prepared pans. Bake for 25–30 minutes or until a toothpick inserted in the center comes out clean.

Cool the Cakes: Let the cakes cool in the pans for 10 minutes before transferring them to a wire rack to cool completely.

Make the Frosting: Beat the cream cheese and butter together until smooth and creamy. Gradually add the powdered sugar, one cup at a time, beating on low speed until fully incorporated. Add the lemon juice, lemon zest, and vanilla extract, then beat on high speed until the frosting is light and fluffy.

Assemble the Cake: Place one cake layer on a serving plate. Spread a generous layer of frosting on top. Repeat with the second and third layers, spreading frosting evenly between each. Frost the top and sides of the cake.

Decorate: Garnish with fresh blueberries, lemon slices, and mint leaves, if desired.