Preheat the oven to 350 degrees. Grease and flour three 8" or 9" round pans.

In the bowl of your mixer, cream together butter, oil, and sugar until light and fluffy, about 5 minutes.

Add the vanilla and egg whites and beat until batter is light and airy, about 5 minutes on medium speed.

In a separate bowl, whisk together flour, baking powder, and salt.

Add half of the dry ingredients to the batter and mix until just combined.

Add the buttermilk and mix until just combined.

Add remaining dry mixture, mixing until combined and scraping down the sides of the bowl.

Evenly spoon batter into prepared pans.

Bake cakes for 22-25 minutes or until a knife is inserted in the center and comes out with only a few coarse crumbs. Remove cakes from oven and cool for 5 minutes in pans, then transfer cakes to a wire cooling rack to cool completely.

Whisk in ¼ cup freeze dried powder to the Swiss Meringue Buttercream frosting.

To assemble the cake, level cakes by cutting off domed tops, if necessary. Place the first cake layer on a cake plate or cake board. Using an offset icing spatula, spread about ½ cup of the strawberry frosting over the cake layer.

Pipe a rim of the frosting around the edge of the cake.

Evenly spread about ¼ cup to ½ cup of the strawberry cake filling inside the frosting barrier.

Repeat with remaining layers.

After you place the final layer, frosting the outsides of the cake. Refrigerate the cake for at least 20 minutes to allow frosting to set.

Right before serving, garnish with fresh strawberries.