Preheat your oven to 350°F (175°C) and then grease and flour two 8-inch round cake pans (or three 6-inch pans).

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

In a large bowl, cream the softened butter and granulated sugar together until the mixture is light and fluffy.

Beat in the eggs one at a time, ensuring each is well incorporated before adding the next. Then, stir in the vanilla extract, lemon zest, and lemon juice.

Gradually add the dry ingredients to the wet mixture, alternating with the buttermilk. Start and finish with the dry mixture, mixing until just combined.

Gently fold in the flour-tossed blueberries into the batter. Be mindful not to overmix.

Divide the batter evenly among the prepared pans and bake for 25 to 30 minutes, or until a wooden skewer inserted into the center comes out clean.

Let the cakes cool in their pans for 10 minutes, then invert them onto a wire rack to cool completely.

In a large bowl, beat the softened cream cheese and butter until smooth and creamy.

Gradually add the sifted powdered sugar, mixing until you reach a smooth consistency.

Stir in the vanilla extract, lemon zest, lemon juice, and a pinch of salt.

Once the cakes are completely cooled, frost and decorate as desired. A sprinkle of fresh blueberries and slices of lemon on top adds the perfect finishing touch.