Ingredients:

  • 2 cups (250g) all-purpose flour
  • 2 cups (400g) granulated sugar
  • 3/4 cup (75g) unsweetened cocoa powder
  • 1 tsp (5g) baking soda
  • 1/2 tsp (3g) baking powder
  • 1/2 tsp (3g) salt
  • 1 tsp (2g) ground cinnamon
  • 2 large (100g) eggs
  • 1/2 cup (120ml) vegetable oil
  • 1 cup (240ml) buttermilk
  • 2 cups (230g) grated zucchini, squeezed lightly
  • 1 cup (170g) semi-sweet chocolate chips
  • 1/2 cup (115g) unsalted butter, melted
  • 1/3 cup (30g) unsweetened cocoa powder
  • 3 cups (600g) powdered sugar
  • 1/3 cup (80ml) whole milk
  • 1 tsp (5ml) vanilla extract

Instructions:

  1. Preheat oven to 350°F (175°C). Grease a 13x9 inch pan thoroughly with butter or line it with parchment paper.
  2. Grate the zucchini using the fine side of the grater and give it a light squeeze with a paper towel to remove pooling water without drying it completely.
  3. Whisk together the flour, sugar, cocoa, baking soda, baking powder, salt, and cinnamon in a large bowl until no lumps remain.
  4. In a separate bowl, beat the eggs, oil, and buttermilk until smooth.
  5. Fold the wet ingredients into the dry ingredients until just combined.
  6. Stir in the grated zucchini and chocolate chips using a rubber spatula.
  7. Spread the batter evenly into the prepared pan, smoothing the top with an offset spatula.
  8. Bake for 22-28 minutes. Use a toothpick to check the center; it should come out with a few moist crumbs.
  9. Allow cake to cool on a wire rack. Prepare frosting by combining melted butter, cocoa powder, powdered sugar, milk, and vanilla extract, then spread evenly over the cooled cake.