For the Cake Layer:

1. Preheat the oven to 350°F. Grease and flour two 8-inch cake pans.
2. In a large mixing bowl combine the cake ingredients: cake mix, pudding mix, milk, vegetable oil, eggs, egg white, vanilla extract and lemon zest. Beat on medium-high speed until all of the ingredients are well mixed.
3. Pour the batter into the prepared pans, dividing evenly.
4. Bake at 350°F for 25-30 minutes. Test your cake for doneness by inserting a toothpick into the center of the cake. If the toothpick comes out clean, then your cake is done. Allow the cake to cool completely.

For the Lemon Ice Cream:

1. Prepare the whipped cream first. Place a medium-sized metal mixing bowl in the freezer for 5-10 minutes to chill.
2. Pour the heavy whipping cream into the chilled bowl and beat on medium-high speed until the heavy cream starts to thicken.
3. Next, slowly add the powdered sugar and continue beating on high speed until stiff peaks form. Set the whipped cream in the refrigerator for later.
4. Beat the softened cream cheese on medium-high speed for 2-3 minutes until the cream cheese is smooth and free of lumps. Scrape down the sides of the bowl as needed.
5. Add the dry instant lemon pudding mix and 2 tablespoons of heavy whipping cream. Beat on medium high speed for two minutes until pudding is well mixed into cream cheese. The cream cheese will thickened. You can add additional tablespoons of heavy cream until the cream cheese is softened so it will easily mix into lemon filling.
6. Add the vanilla extract and lemon zest. Beat on medium speed until well combined.
7. Finally, fold in the prepared whipped cream, turning the filling over from the bottom to the top and continuing to stir until it’s well mixed.

To Assemble the Cake:

1. Use a springform pan or your cake pan that is the same size as your cakes (in this case, 8 inches). Wrap the edges of the pan with saran wrap. Place a cake board in the bottom of your pan, under the saran wrap.
2. Tort the top of each cake layer so that it is completely flat using either a cake leveler or a serrated knife. Place the first layer on top of your cake board.
3. Pour the ice cream base over top of the cake and spread evenly with a spatula.
4. Place the second layer of cake on top. Freeze for at least 4 hours until the ice cream layer is completely frozen.
5. Sometimes, the cake shrinks when it’s baked, so the edges of the ice cream are wider than the cake. Shave the edges of the cake if you need to even them out by using a hot serrated knife.

To Frost the Cake:

1. Spread the Cool Whip with an angled spatula, covering the surface of the cake as evenly as possible. If you decide apply more than one layer of frosting, it’s easier to add one layer, refreeze for an hour and then add another layer and freeze again.
2. Pipe the boarder of the cake using a large open start tip. You may have leftover Cool Whip.
3. This cake should be kept in the freezer, and it is best kept in a freezer-safe cake container.