Position an a rack in the center of the oven and preheat oven to 350F degrees. Lightly mist a bundt pan with vegetable oil spray. Dust with flour, shake out the excess flour and set the pan aside.
In a large mixing bowl, combine the mashed bananas, cake mix, flour (if using), oil, yogurt, eggs and vanilla.
Beat with an electric mixer on low speed until the ingredients are incorporated, about 30 seconds.
Stop the mixer and scrape down the sides of the bowl with a rubber spatula. Beat on medium speed until the mixture lightens and is smooth, about 1-1/2 minutes longer.
Stir in the chocolate chips.
Pour the batter into the prepared cake pan. Smooth out the top with a rubber spatula.
Bake the cake until is deeply golden brown on top and the top springs back when lightly pressed with your finger, 50 to 55 minutes.
Remove the cake from the oven and let it cool on a wire rack for 10 minutes. Run a long sharp knife along the edges of the pan. Shake the pan to loosen the cake and then invert it onto the rack.
While the cake is still warm, sift the confectioners sugar over the top so that it melts to form a glaze.
Let the cake cool for 20 minutes, then slice and serve while still a little warm.
Notes
Serving size: 1 sliceWW Points: 9Check your WW Points for this recipe and track it in the WW app. (Must be logged into WW on a smartphone or tablet.)9SmartPoints (Green plan)8SmartPoints (Blue plan)8SmartPoints (Purple plan)6PointsPlus (Old plan)I made a few changes to the original recipe to lighten it up and make it a little more Weight Watchers friendly.I omitted the additional 1/4 cup of sugar called for since cake mixes are plenty sweet for us. Replaced the sour cream with plain non-fat Greek yogurt and increased it by 1/4 cup and decreased the oil by 1/4 cup.I also added 2 tablespoons of flour which is a trick my mother learned from her Home Economics teacher decades ago to help cake mix cakes be less crumbly.