1/2 cup Semi-sweet chocolate chips
3 Ripe bananas, mashed
1 tsp. Pure vanilla extract
1/4 cup Sour cream
1 Large egg plus egg yolk
1 cup Granulated sugar
1/2 cup Unsalted butter
1/2 tsp. Kosher salt
1 tsp. Baking soda
2 cups All-purpose flour