Step 1

Preheat the oven to 275°F.

Step 2

Grease and flour a 9x13 mold.

Step 3

Mix the banana and the lemon juice in a clean bowl. Reserve.

Step 4

Mix all the dry ingredients in a separate bowl: the flour, salt, and baking soda.

Step 5

Beat the butter and sugar with an electric mixer until you get a smooth and creamy mixture.

Step 6

Add the eggs one at a time, and then add the vanilla.

Step 7

Add the dry ingredients and buttermilk alternating between the two. Add the banana mixture and continue beating until everything is properly integrated.

Step 8

Pour the batter over the prepared pan, and bake for an hour. Remove from the oven and immediately place in the freezer for 45 minutes.

Step 9

Beat the butter with an electric mixer with the cream cheese until smooth. Add a tablespoon of vanilla. Add the icing sugar little by little and continue beating until smooth.

Step 10

When the cake is completely cool, garnish with the frosting and top with the chopped walnuts.

Step 11

Enjoy!