• Preheat the oven to 350°F/175°C and prepare a 9x13 baking pan by coating it with cooking spray.

For the Zucchini Cake

• Cut off the root ends of the zucchini and use a shredder to shred. Place it on a kitchen towel and sprinkle it with a pinch of salt. Let the shredded zucchini sit for 15 minutes. The salt will cause it to drain its liquids.
  
• In a large bowl, combine the flour, sugar, starch, cocoa, baking powder, soda, coffee, and salt. Stir together.
  
• In a separate bowl, stir together the oil, yogurt, vinegar, and vanilla.
• Press the zucchini to remove excess lquids and use a paper towel to dry it off.
• Pour the yogurt mixture in with the flour mixture and stir to combine. Add the chocolate chips and zucchini and stir until just combined.
  
• Use a spatula to spread the batter evenly across the prepared pan. Bake for 35 to 40 minutes. Insert a tester in the middle of the cake. When it comes out clean, the cake is done. Remove from oven and set aside to cool completely before frosting.
  

For the Whipped Ganache Frosting

• If using a chocolate bar, chop it into chunks and place them in a bowl. Pour the milk into a pyrex measuring cup and microwave until hot (but not boiling), about 1 minute. Pour the hot milk over the chocolate and stir it gently to make sure the chocolate is coated. Place a plate and set it aside for up to 5 minutes to allow the chocolate to melt.
• Once the chocolate melts, stir it all together. Transfer the bowl to the fridge for 30 minutes or so until the chocolate is firm but still malleable. Scoop it into a mixing bowl and mix on medium speed for 1 to 2 minutes until light and fluffy.
• When the cake has cooled, spread with whipped ganache frosting.
  
• To store cake, cover and keep refrigerated. It will keep up to 5 days in the fridge.