Here is the vanilla bean buttercream recipe I used with the white on white cake.
Slice open a vanilla bean and scrape out all the little seeds.
Throw some softened butter into a mixing bowl.
Add the vanilla bean seeds and powdered sugar and whip it up.
It’s that easy! You can make this ahead of time or even freeze it. Just make sure you let it sit out and get up to a spreadable consistency before using it. Make sure you put your cake or cupcakes in the refrigerator if you are not planning on eating them right away. The butter will cause this frosting to melt.
Recipe: Vanilla Bean Buttercream
1 1/2 sticks butter, softened
1 tsp vanilla extract, plus 1 vanilla bean
3 1/2 – 4 cups powdered sugar
If the frosting is too thick you can add in milk a tiny bit at a time until you reach desired consistency.
Mikey's In My Kitchen 
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