• Preheat oven to 350 degrees F. Grease an 8 inch square pan and line with a piece of parchment.
• Mix together the flour, cocoa powder, baking soda and salt and set aside.
• In a mixing bowl, mash the bananas. If you weighed them, you won't need to measure the volume, just mash 180 to 190 grams of peeled banana. Add the sugar and beat by hand until well mixed, then beat in the egg white and the vanilla.
• Add the buttermilk and the flour mixture and beat by hand just until blended. Batter will probably be a little lumpy. Stir in about half the chocolate chips (if using, and I recommend using).
• Spread batter evenly in the pan. Sprinkle with the remaining chocolate chips.
• Bake for 25 to 30 minutes or until cake appears set. Let cool and serve by itself or frost with your favorite frosting.

Tofu Chocolate Frosting

• Melt the chocolate chips in the microwave using 50% power and stirring ever 40 to 60 seconds. Set aside to cool slightly.
• Puree the tofu (or use tofu that's alreay been pureed) and put it in a mixing bowl. Whisk in the milk, maple syrup and vanilla. Make sure that this mixture is room temperature and not too cold.
• Whisk melted chocolate (okay if it's just slightly warm) into the tofu mixture. Add vanilla.
• The frosting will be pretty thin at this point, so cover the bowl and chill for an hour or until it is thick enough to spread. You can check it every so often and give it a stir. If you have a large pastry bag, you can fit your pastry bag with a tip, pour the icing into the bag, prop it up in a glass and chill the glass with the frosting filled pastry bag until frosting is thick enough to pipe.