01 - Preheat your oven to 350°F. Grease and line three 8-inch round cake pans with parchment paper.
02 - In a medium bowl, thoroughly whisk together the all-purpose flour, baking powder, baking soda, and salt.
03 - In a large mixing bowl, using an electric mixer, beat the softened unsalted butter and granulated sugar until the mixture is light and fluffy, approximately 3 minutes.
04 - Add the large eggs to the butter and sugar mixture one at a time, ensuring each egg is fully incorporated before adding the next.
05 - In a separate bowl, combine the whole milk, pink lemonade concentrate, fresh lemon juice, and finely grated lemon zest. Whisk gently to combine.
06 - With the electric mixer set to low speed, gradually add the dry flour mixture to the butter mixture in three alternating additions with the liquid lemonade mixture. Begin and end with the dry ingredients, mixing only until just combined to avoid overworking the batter.
07 - If desired, incorporate a few drops of pink food coloring into the cake batter to achieve a subtle pastel pink hue.
08 - Divide the prepared batter evenly among the three lined cake pans. Smooth the tops with a spatula. Bake for 25–30 minutes, or until a wooden toothpick inserted into the center of a cake layer comes out clean.
09 - Allow the baked cake layers to cool in their pans for 10 minutes before inverting them onto wire racks to cool completely to room temperature.
10 - For the buttercream, beat the softened unsalted butter in a large bowl until creamy. Gradually add the sifted powdered sugar, mixing until smooth. Incorporate the pink lemonade concentrate, fresh lemon juice, and a pinch of salt. Beat until the buttercream is light and fluffy, adding the heavy cream for desired consistency if needed. Tint with pink food coloring if desired.
11 - Once the cake layers are completely cool, place one layer on a serving plate or cake stand. Spread a generous amount of pink lemonade buttercream over the top. Repeat this process with the remaining cake layers. Use the remaining buttercream to frost the sides and top of the assembled cake, creating a smooth finish.
12 - Decorate your Pink Lemonade Layer Cake with fresh lemon slices, festive sprinkles, or edible flowers, if desired, before serving.