Preheat your oven to 350°F (175°C) and grease two 9-inch round cake pans. In a large mixing bowl, whisk together all-purpose flour, baking powder, and baking soda.

In another bowl, mix buttermilk, eggs, vanilla extract, and fresh lemon juice until smooth. Gradually combine the wet and dry ingredients, stirring until just incorporated.

Gently fold in the blueberries, being careful not to break them.

Evenly divide the batter into the prepared cake pans. Bake in the preheated oven for 30-35 minutes.

Check for doneness by inserting a toothpick; it should come out clean. Let the cakes cool for about 10 minutes before transferring to wire racks.

While the cakes cool, whip the heavy cream with an electric mixer until soft peaks form. Fold in lemon juice and zest.

Once cooled, place one cake layer on a serving plate and spread frosting on top. Add second layer and frost the top and sides of the cake.

Chill the frosted cake in the refrigerator for about 30 minutes before serving.