Start by preheating your oven to 375 degrees F.
Grease a 13x9 inch cake pan.
Then start mixing your banana bread cake ingredients. Beat together the sugar, sour cream, eggs, and butter until creamy.
Add in your mashed bananas and vanilla extract. Stir well.
Then add in your dry ingredients of flour, baking soda, and salt.
Mix well then stir in the pecans.
Spread into your prepared pan and bake for 25 minutes or until brown. Test to see if the cake is done with a toothpick before removing from oven.
Cool a few minutes before adding frosting.