Preheat the oven to 350. Grease one 9x5 pan or two 8x4 pans.
In a small bowl, mash bananas, brown sugar, vanilla extract, and ground cinnamon.
In a large bowl, cream butter and sugar together until light and fluffy.
Add in eggs and beat until mixed.
To the wet ingredients, sift in flour, baking soda, and salt.
Stir until just combined.
Pour in mashed bananas, and mix until combined. Add in chocolate chips; stir.
Bake at 350 for 35-40 minutes (for two 8x4 pans) or until cake tester comes out clean with just a few moist crumbs stuck to it. If using one 9x5 pan, bake at 350 for 30 minutes; then lower the temp to 325 and bake for 15-20 or until cake tester comes out clean with just a few moist crumbs stuck to it.
Allow to cool for 10 minutes. Move to a wire cooling rack.