This Chocolate Zucchini Cake with Chocolate Buttercream is exactly what every chocolate cake should be: rich and decadent! It's an easy sheet cake recipe that ends up incredibly tender and sweet. A great chocolate dessert for everyone to enjoy!
Preheat oven to 350°F and grease a 9x13 cake pan or baking dish.
In a stand mixer or with hand beaters, beat together the sugar and eggs until pale yellow and fluffy.
Add the canola oil and vanilla extract, beat well.
Add the whole wheat flour, cocoa powder, baking powder, baking soda and salt. Mix on low just until combined.
Beat the buttermilk in on low until fully incorporated.
Fold in shredded zucchini, scraping the sides of the bowl and ensuring everything is completely combined.
Pour the batter into prepared cake pan and bake for 35-45 minutes until toothpick inserted in the center comes out clean.
Let cake cool completely before frosting.
For the Frosting
Beat softened butter until fluffy.
Add the cocoa powder, vanilla extract and half of the powdered sugar. Beat until everything is incorporated.
Add the remaining powdered sugar and milk. Beat on low just until everything is mixed together being sure to scrape the sides of the bowl.
Increase the speed to medium and beat for 2-3 minutes until light and fluffy.
Frost cooled cake and serve.
Notes
To make a layered cake: bake in two 9 inch round cake pans for 20-25 minutes or until toothpick inserted in center comes out clean. Double the frosting recipe to have enough for the filling and sides of cake.