In a medium bowl, combine the flour, baking powder and baking soda.
In a large bowl, with an electric mixer at medium speed, beat the sugar, applesauce, eggs and oil until frothy. With the mixture at low speed, alternately add the bananas and buttermilk with the flour mixture; stire until just combined (do not overmix).
Fold in the chocolate chips.
Spoon the batter into the cups, filling each about two-thirds full.
Bake until golden and a toothpick inserted in the center comes out clean, 20-25 minutes.
Remove from the cups and cool completely on a rack.