Preheat the oven to 325F. Spray a 9×5" loaf pan with cooking oil (or two smaller loaf pans – the pan should have at least a 1" rim after it is filled)

Add the butter to a medium saucepan over medium heat. Melt the butter and continue cooking, stirring occasionally until the butter starts to foam. Once it foams, continue stirring or swirling the pan until golden flecks form. Once golden and toasty smelling, pour into a bowl to stop the browning and set aside

In a bowl, mix together flour, cornstarch, baking powder, baking soda, and spices

In another bowl, mash the ripe bananas with a fork until mostly smooth. Add in the eggs, vanilla, and salt. Mix well and set aside

In the base of a stand mixer with a paddle attachment or with a hand mixer, beat the butter and sugars until light and fluffy, around two minutes. Scrape down the sides and mix again for about 30 seconds

Add in the banana mixture and beat until incorporated. Scrape down the sides and mix again for about 30 seconds

Pour in the dry ingredients and pulse together until just combined. Mix in the chocolate chips until incorporated

Pour batter into the prepared baking pan

Bake for 75-90 minutes, or until a tester poked into the center comes out clean (depending on your oven and baking pan it may take longer or shorter, we recommend to start testing after ~1 hour)

Note: if using multiple smaller pans reduce the bake time