Preheat the oven to 350°F (175°C) and grease and flour two 9-inch cake pans.
In a medium bowl, whisk together the flour, baking powder, and salt.
In a separate bowl, cream the butter and sugar together until light and fluffy, about 3-4 minutes.
Beat in the eggs one at a time, followed by the vanilla extract and lemon zest.
Gradually add the dry ingredients, alternating with the milk, and mix until just combined.
Divide the batter evenly between the two prepared cake pans and bake for 30-35 minutes, or until a toothpick inserted into the center comes out clean.
Let the cakes cool in the pans for 10 minutes, then transfer to a wire rack to cool completely.
For the buttercream, beat the butter until creamy. Gradually add powdered sugar, heavy cream, lemon juice, and beat until smooth and fluffy.
Once the cakes are cool, spread a layer of buttercream on top of one cake, then place the second cake on top. Frost the top and sides of the cake with the remaining buttercream.
Garnish with extra lemon zest or edible flowers, if desired. Slice and enjoy!
Notes
This cake can be decorated with lemon slices or fresh flowers for an extra touch of elegance.