Preheat the oven to 350˚F. Lightly spray a 9×13 inch baking dish. Set aside.
In a large bowl, cream together the butter and sugar until light and creamy. Add the eggs in one at a time, mixing until fully combined. Mix in the mashed bananas until incorporated.
Add in the remaining ingredients and mix together until fully combined.
Pour the cake mixture in the prepared baking dish, and bake in the preheated oven for 45 minutes, or until a toothpick inserted in the center comes out clean.
Notes
For the best flavor, use very ripe bananas with lots of brown spots.
Be careful not to overmix the batter. This will create a dense cake. Just mix until the dry ingredients are just combined.
Store this cake at room temperature for 3 days, or in the fridge for up to 7 days.
This cake freezes well. To freeze, you can wrap individual slices or the whole cake in plastic wrap then aluminum foil. Freeze for up to 3 months.