Cut off golden crust on cakes for a truly "white cake" presentation when sliced.
Store buttercream in fridge if not using right away. Re-beat upon removal to bring back to spreading consistency.
This is a very scant amount of buttercream for a 6-layer cake. Try to use it sparingly, or make more if you'd like to not have to scrimp on frosting.
Decorate with lilacs right before serving to ensure lilac flowers do not wilt.
Serve cake at room temperature.
Recipes barely, barely adapted from the awesome
Sweetapolita Bakebook.