Preheat oven to 350.
Line three 8" pans with parchment rounds and grease with Pam.
In a mixer bowl, place the flour, sugar, baking powder and salt. Mix.
Add the butter in on low until crumbly.
Add egg whites.
Add buttermilk in two additions.
Add oil and vanilla.
Divide into pans. (Can use baking strips for pans if you have, I did.)
Bake approx 35 mins.
Cool 10 mins in pan and run a knife around the edges.
Freeze in pans 30 mins and then flip cake out of pans.
At this point you can freeze the layers, wrapped until ready to decorate.
Frost while frozen!
Once candies are in, you must store this in the fridge or the candy weight will push the sides down.