Preheat oven to 350 degrees F
Grease 2- 7inch cake pans, line bottom with parchment, grease parchment and flour pans.
In medium bowl combine the egg whites, 1/4 cup milk and vanilla.
In large bowl of mixer add the dry ingredients (flour, sugar, baking powder, salt).
Mix the dry ingredients for 30 seconds to combine.
Add the butter and the remaining 3/4 cups milk, mixing on low until ingredients are moistened.
With mixer on medium speed beat for 1.5 minutes to form the cake batters structure.
Scrape down the sides.
Slowly add the egg mixture in 3 batches, mix 20 seconds after each addition.
Scrape down the sides with spatula.
With mixer on medium slowly add the melted chocolate and mix until well combined.
Pour batter into cake pans evenly.
Bake 44-48 minutes or until golden brown and toothpick inserted comes out clean.
Let cool completely.
In medium sauce pan add the egg whites and sugar.
On medium heat you are going to whisk egg mixture until sugar is completely dissolved (you can test it by rubbing a small amount between your fingers to test it, it should be completely smooth).
Transfer to mixing bowl and with whisk attachment whisk on high until stiff peaks form and mixture is completely cooled.
Switch to paddle attachment.
On low speed add the butter one piece at a time. Mix until well combined.
Add in the vanilla, continue mixing until completely mixed in.
Cut each cake horizontally so you have a total of 4 layers.
Put a small dollop of frosting on cake board/cake plate so the cake sticks.
Put on the first layer, spread layer of buttercream, smooth with offset spatula.
Sprinkle with 1/4 cup crushed candy cane.
Repeat with next two cake layers.
Place last layer of cake on top.
Crumb coat the cake, refrigerate.
Apply and smooth out final coat of buttercream on top and sides. Pipe on top and bottom border.
sprinkle with remaining crushed candy cane.
Decorate with flowers.