Preheat your oven to 350°F (175°C) and grease two 9-inch round cake pans with butter and flour.

In a large bowl, cream together the softened butter and granulated sugar until smooth. Add the eggs, one at a time, beating well after each addition. Stir in the lemon juice and zest.

In a separate bowl, whisk together the flour, baking powder, and salt.

Gradually add the dry ingredients to the butter mixture alternately with the milk, starting and ending with the flour. Mix until just combined.

Divide the batter evenly between the greased pans and bake for 25-30 minutes or until a toothpick inserted in the center comes out clean. Let the cakes cool in the pans for 10 minutes before transferring to a wire rack to cool completely.

In a mixing bowl, whip the heavy cream until soft peaks form. Gradually add the powdered sugar, vanilla extract, and lemon zest, then continue to whip until stiff peaks form.

Once the cakes have cooled, place one layer on a serving plate. Spread half of the lemon cream over the top, then add the second layer. Top with the remaining lemon cream and garnish with lemon slices and mint if desired.