Preheat oven to 325 degrees F. Spray three 8-inch round cake pans with nonstick spray, line the bottom with parchment paper and spray again. Set aside.
In a medium-size mixing bowl, whisk together the cake flour, baking powder, salt, and baking soda. Set aside.
In the bowl of a stand mixer fitted with the paddle attachment, or using a hand mixer, beat the butter, oil, and sugar on medium-high until smooth and fluffy, about 2 minutes.
With the mixer on medium-low speed add the vanilla, strawberry emulsion or extract (if using), and the eggs and egg whites. I like to add the eggs one or two at a time and then mixing the batter for a few seconds to let the ingredients get incorporated. It’s also good to turn the mixer off and scrape down the sides and bottom of the bowl between additions too.
After the eggs are added, turn the mixer to medium-high and beat the cake batter for about 1 to 2 minutes, until the mixture is smooth and fluffy.
Gradually add the strawberry puree and continue to mix for another minute or so.
With the mixer on low, alternately add the dry ingredients and the buttermilk, starting and ending with the flour mixture. Stir just until no streaks of flour remain.
Stir in 1 to 2 drops of pink food coloring, if desired.
Evenly distribute the batter between the three pans, about 17-18 ounces in each. Bake for 30-35 minutes or until a toothpick inserted in the center of the cake comes out with a few moist crumbs on it.
Cool the cakes on cooling racks for about 15 minutes before inverting onto write racks to cool completely.