Step 1

Preheat oven to 350 degrees. Spray 3 (9-inch) round cake pans with baking spray with flour.

Step 2

In a large mixing bowl, combine flour, sugar, baking soda, and salt.

Step 3

Add oil, buttermilk, eggs, and vanilla extract and beat on medium-low speed with an electric mixer until smooth.

Step 4

Beat in mashed banana.

Step 5

Pour batter into prepared pans doing your best to fill them with equal amounts.

Step 6

Place in oven and bake 20 to 25 minutes or until a wooden toothpick inserted in center comes out clean.

Step 7

Let cakes cool in pans for 10 minutes and then remove to wire racks to cool completely.

Step 8

Place pudding mix and cream cheese in a medium bowl and beat with a mixer set to low speed until smooth. Gradually add in cream and beat until mixture is very thick.

Step 9

Arrange about 15-18 vanilla wafers on top of one of the cake layers. Use a spatula to spread half of the pudding mixture on top of the wafers. Top with 1/2 of the banana slices placed in a single layer.

Step 10

Place a second layer of cake on top of bananas, and repeat layers: vanilla wafers, pudding mixture, and bananas.

Step 11

Top with final layer of cake.

Step 12

Make frosting. Beat butter in a large bowl until creamy. Slowly add confectioners' sugar, beating until smooth. Add whipped topping and beat until evenly mixed in.

Step 13

Spread frosting over top and sides of cake. Decorate with vanilla wafers.

Step 14

Cover with plastic wrap and refrigerate up to 3 days.