Preheat your oven to 180°C (350°F). Grease two 8-inch round cake pans and line with parchment paper for easy removal.
In a large bowl, sift together the cake flour, baking powder, and salt. Set aside.
In another bowl, beat the softened butter and granulated sugar on medium speed until the mixture is pale, fluffy, and fragrant, about 3-4 minutes.
Add eggs one at a time, beating well after each addition until the batter is smooth and slightly thickened. Scrape down the sides of the bowl as needed.
Stir in vanilla extract and lemon juice, blending until fragrant and bright.
Reduce mixer speed to low. Alternately add the dry ingredients in three parts and buttermilk in two parts, beginning and ending with dry, mixing just until combined.
Divide the batter evenly between the prepared pans and smooth the tops with a spatula. Gently tap the pans to release air bubbles.
Bake for 25-30 minutes, until the edges are golden and a toothpick inserted into the center comes out clean. The cakes should spring back when pressed lightly.
Let the cakes cool in the pans for 10 minutes, then transfer to a wire rack to cool completely before frosting.
While the cakes cool, puree the hulled strawberries until smooth. Strain to remove seeds for a silky buttercream.
In a bowl, beat the softened butter until creamy. Gradually add sifted powdered sugar, beating on low, then mix in the strawberry puree and vanilla until fluffy and smooth.
Once the cakes are cooled, spread a layer of buttercream on the first cake. Add sliced strawberries on top if desired, then place the second layer and frost the entire cake generously.
Decorate with additional fresh strawberries or piping as preferred. Chill the cake for 30 minutes to set the frosting before serving.
