NOTE: 8×3-inch springform pans are best for building this cake so that you can easily remove the cake once it’s been assembled. If you do not have a springform pan, line your cake pan with clear wrap before adding your parchment paper and cake board. You can use the clear wrap to lift your cake out of the pan once it’s assembled and frozen. You want to make your cake layers in the same pan you’ll use for layering the ice cream and cake together so that the cake layers fit in the final pan you use for layering. In lou of using a cake pan to build the cake, you could also use cake collars.

TO MAKE THE CAKE LAYERS:

1. Prepare an 8 inch springform or cake pan with a parchment paper circle in the bottom and grease the sides. Preheat oven to 350°F (176°C).
2. In a large mixing bowl, cream butter and sugar together until light in color and fluffy, about 3-4 minutes. Do not skimp on the creaming time.
3. Add sour cream and vanilla extract and mix until well combined.
4. Add egg whites in two batches, mixing until well combined after each. Scrape down the sides of the bowl as needed to be sure all ingredients are well incorporated.
5. Combine dry ingredients in a separate bowl, then combine the milk and water in a small measuring cup.
6. Add half of the dry ingredients to the batter and mix until well combined. Add the milk mixture and mix until well combined. Add remaining dry ingredients and mix until well combined. Scrape down the sides of the bowl as needed to be sure all ingredients are well incorporated.
7. Pour the batter evenly into the cake pan and bake for about 29-31 minutes, or until a toothpick comes out with a few crumbs.
8. Remove the cake from the oven and allow to cool for about 3-5 minutes, then remove to a cooling rack to cool completely.

TO MAKE THE ICE CREAM:

9. When the cake is cool, make the ice cream. Combine the milk and pudding mix and whisk until well combined and smooth.
10. In a large mixer bowl, combine the cream cheese and sugar and mix until smooth.
11. Stir in the pudding mixture until smooth. Set aside.
12. In another mixer bowl, add the heavy whipping cream and powdered sugar and whip on high speed until stiff peaks form.
13. Gently fold about 1/3 of the whipped cream into the cream cheese mixture until combined, then fold in the remaining whipped cream.
14. Gently fold in half of the chopped bananas and 1/3 of the crushed vanilla wafers until combined throughout.

ASSEMBLY:

15. Line the sides of an 8-inch springform pan with parchment paper. The parchment paper should stick up above the top edge of the pan, since the cake will probably be a little taller than your pan (see this example). If you want, put a cardboard cake circle in the bottom of the pan. If not using a springform pan, you pan put some plastic wrap in the bottom of the pan and up the sides and use it to lift the cake out of the pan when it’s done.
NOTE: You should be using the same 8-inch pan you used for the cake. Not all 8-inch pans are exactly the same size. Your cake needs to fit in this pan.
16. Cut the dome off of the top of the cake layer, then cut the cake into two layers. Place the first cake layer into the bottom of the pan.
17. Sprinkle half of the remaining chopped bananas and another 1/3 of the crushed vanilla wafers over the cake layer.
18. Spread the ice cream mixture evenly over the bananas and wafers.
19. Sprinkle the remaining chopped bananas and crushed vanilla wafers over the ice cream and pat them down into the ice cream so they are flush with the ice cream.
20. Top the ice cream with the other layer of cake.
21. Freeze cake until firm, 6-8 hours or overnight. Once frozen, remove from springform pan and remove parchment paper from sides.
22. To make the whipped cream frosting, whip the heavy whipping cream, powdered sugar, vanilla extract and yellow food coloring until stiff peaks form.
23. Frost the outside of the cake with the whipped cream, then pipe a border around the top edge.
24. To finish off the cake, press crushed vanilla wafer crumbs onto the sides of the cake and top it with banana chips, if desired.
25. Freeze the cake until ready to serve. Allow to thaw for 45 minutes to an hour before serving.