Preheat the oven to 325 degrees. Spray two 8-inch cake pans with nonstick cooking spray and set aside.
In a large mixing bowl whisk together, cake mix, all-purpose flour, and granulated sugar.
With an electric hand mixer or a whisk, mix dry ingredients on low.
Slowly, add in water, sour cream, eggs, egg white, heavy cream, and vegetable oil, and mix.
Mix both wet and dry ingredients all together until well-combined.
Divide cake batter between two 8-inch cake pans.
Bake in preheated oven for 25 minutes or until the center is baked.
Remove from the oven and allow to cool for 15 minutes on a cooling rack.
Use a fork or a bamboo stick to poke holes all over the cake.
In a mixing bowl add 1 cup of boiling water and stir in strawberry Jell-o until dissolved. Repeat with the berry blue Jell-O in a separate mixing bowl.
Pour strawberry Jell-O carefully over one of the baked cakes. Carefully, pour berry blue Jell-O over the other cake.
Cover cakes and refrigerate for 4 hours or overnight.
With an electric mixer, cream together butter and shortening until smooth and creamy, about 3 minutes.
Add in heavy whipping cream and coconut extract.
Slowly, add in confectioner’s sugar a little at a time. If frosting is too thick you can add 1 teaspoon of heavy whipping cream until you have reached the texture, you are looking for. Mix frosting for another 2 minutes.
Remove cakes from cake pans. Place 1 cake layer on a cake stand and spread about 1 cup of frosting on top.
Place remaining cake on top of frosting. Spread the top and the sides with frosting until the cake is completely covered. Decorate the cake with colored frosting or sprinkles.
Place cake in the refrigerator until ready to serve.