Grease a tube pan* with oil and lightly dust with potato starch. Preheat the oven to 350°F.
In a large bowl, beat egg yolks until thickened. Add the sugar and salt slowly, beating constantly, until mixture is lemon colored. Add the mashed banana and potato flour while beating. Once blended, gently mix in chocolate chips with a spatula.
In a separate bowl, beat egg whites until stiff. Gently fold into egg yolk mixture until egg whites are just incorporated. Pour batter evenly into the prepared tube pan and bake for 45 minutes, until cake bounces back when touched and a toothpick comes out clean.
Allow the cake to cool upside down for about 30 minutes. When ready to serve, remove from the pan and place onto a serving platter. Dust with powdered sugar. Serve with fresh berries or fresh sliced bananas, if desired.
Notes
*Note: Be sure to use a traditional tube pan (sometimes referred to as an angel food cake pan) with smooth sides. A Bundt pan is a type of tube pan, but because of the creases on a Bundt pan, this recipe likely won’t rise well in that type of pan.