Using a medium bowl, whisk together the cake flour, baking powder and salt until combined, set aside
Using a standing mixer, cream together the whip together butter and sugar until fluffy.
In separate mixing bowl whisk together milk, egg whites and vanilla extract until well blended.
Add 1/3 of the flour mixture to butter/sugar mixture, then mix until combined, then add 1/2 of the milk/egg mixture and mix on low speed until combined
Add another 1/3 of the flour mixture and mix until combined, then add remaining 1/2 of the milk/egg mixture and mix on low until combined
Add last 1/3 of the flour mixture and mix until well combined.
Split the batter into two bowls and add 1 tsp of the strawberry extract and a few drops of pink food coloring and mix until combined
Gently dollop a heaping 1/8 cup of the strawberry cake mix over chocolate layer
Gently dollop 1/8 C of the vanilla cake mix over the strawberry layer
Bake in the oven for 21 minutes
Allow to cool completely