• Preheat the oven to 350 degrees, lightly spray a 9x13 inch pan with baking spray or lightly butter and flour the pan, set side.
• In a medium sized mixing bowl, whisk together the flour, baking powder, baking soda, and salt, set aside.
• In the bowl of a stand mixer or a large mixing bowl with a hand mixer, add butter. With mixing speed on medium, beat for 2 minutes until creamy. Add sugar and beat on medium speed for two minutes or until light and fluffy.
• Add vanilla extract and coconut extract, mix to combined.
• Add egg yolks, one at a time, mixing well after each addition.
• In a medium mixing bowl, whip egg whites until stiff peaks form, set aside.
• Gradually add dry ingredients to the wet ingredients alternate adding the coconut milk and sour cream, mix just until combined.
• Gently fold in egg whites until no streaks remain.
• Pour batter into prepared baking pan and spread into an even layer.
• Place in the oven to bake for 30-45 minutes or until the top springs back when touched.
• Remove from the oven and allow to cool for 30 minutes before frosting.

Frosting

• In the bowl of a stand mixer or a large mixing bowl with a hand mixer, beat butter on medium speed for 2 minutes or until creamy.
• With mixing speed on low, gradually add the powdered sugar then add vanilla extract, coconut extract, coconut milk, and salt. Beat on medium high speed for 3 minutes. Using an offset spatula or a knife, spread onto cooled cake in an even layer. Top with coconut flakes.