Preheat your oven to 350°F (175°C). Grease and flour the two 9-inch round cake pans.
In a large mixing bowl, combine softened butter and granulated sugar. Beat with an electric mixer on medium speed until light and fluffy.
Add eggs one at a time, mixing well after each addition. Incorporate vanilla extract.
In another bowl, whisk together the flour, baking powder, and salt.
Gradually add the dry ingredients to the butter mixture, alternating with milk. Start and end with the flour mixture, mixing until just combined.
Divide the batter evenly between the two prepared cake pans. Bake in the preheated oven for 25 minutes or until a toothpick inserted in the center comes out clean.
Allow the cakes to cool in the pans for 10 minutes before transferring them to wire racks to cool completely.
Once cool, place one cake layer on a cake stand. Spread a layer of frosting on top, then place the second cake layer on it.
Cover the entire cake with a thin layer of frosting to create a crumb coat. Refrigerate for 15 minutes to set.
Once set, frost the cake generously with the remaining frosting. Use an offset spatula for a smooth finish.
Decorate the top of the cake with the green coconut shavings to mimic grass. Arrange the Peeps chicks on top and around the cake to create a garden scene. Add edible flowers or candy as desired.
Use toothpicks to secure the Peeps if needed, ensuring they stay upright.