• Mix together cake mix, egg whites, water and oil for 2 minutes on medium speed.
• Grease three 9 inch round pans and line the bottom with a circle of parchment. Divide the batter into the three pans.
• Bake at 350 degrees for about 15 minutes.
• Allow the cakes to cool for 15 minutes and then flip them over on a cooling rack, peel off the parchment and flip them right side up again to finish cooling.

Whipped Cream:

• Beat heavy cream and vanilla until peaks form, set in fridge.

Cream Filling Base:

• Beat softened cream cheese.
• Add powdered sugar and marshmallow cream.
• Set aside.

Strawberry Cream Filling:

• Puree 1 cup of hulled strawberries in a blender or food processor to make 1/2 cup strawberry puree.
• Gently fold together 1 cup of the cream filling base, 1 1/3 cups of the whipped cream and 1/2 cup of strawberry puree.

Blueberry Cream Filling:

• Puree 1/2 cup of blueberries in a blender or food processor to make 1/4 cup blueberry puree.
• Gently fold together 1/2 cup of the cream filling base, 2/3 cups of the whipped cream and 1/4 cup of blueberry puree.

Assembly:

• Place one cake round on a cake stand and top it with half of the strawberry cream filling and 1/2 cup of diced strawberries.
• Add another cake and top it with the blueberry cream filling and 1/2 cup of blueberries.
• Top with the final cake and half of the strawberry cream filling.
• Circle the top of the cake with quartered strawberries and put blueberries in the middle.
• Store in fridge until ready to serve.