Vegan Chocolate Sheet Cake

4.94 from 16 votes

Rich, moist and decadent vegan chocolate sheet cake with a rich chocolate frosting. Perfect for special occasions or just to satisfy a chocolate craving.

Prep Time15

Cook Time30

Total Time45

Course: Cakes, Dessert

Cuisine: American

Diet: Vegan

Servings:

Calories: 382kcal

Author: Alison Andrews

Ingredients

For the Sheet Cake:

2 cups All Purpose Flour (250g)
¾ cup Cocoa Powder (65g) Unsweetened
1 cup White Granulated Sugar (200g)
½ cup Light Brown Sugar (100g)
1 teaspoon Baking Soda
½ teaspoon Salt
1 ½ cups Vegan Buttermilk (360ml) 1 ½ Tablespoons Lemon Juice + Soy Milk up to the 1 ½ cup line
1 Flax Egg 1 Tablespoon Ground Flaxseed + 3 Tablespoons Hot Water
½ cup Canola Oil (120ml) or Vegetable Oil
1 Tablespoon Distilled White Vinegar or Apple Cider Vinegar
2 teaspoons Vanilla Extract

For the Chocolate Fudge Frosting:

½ cup Vegan Butter (112g)
3 cups Powdered Sugar (360g)
¾ cup Cocoa Powder (65g)
1 teaspoon Vanilla Extract
4-5 Tablespoons Soy Milk or other non-dairy milk.

For Decoration (Optional):

Vegan Chocolate Shavings

Instructions

Preheat the oven to 350°F (180°C) and spray a 9x13 baking pan (*see notes for different sizes) with non-stick spray.
Sift all purpose flour and cocoa powder into a mixing bowl. Add white granulated sugar, light brown sugar, baking soda and salt and mix together.
Prepare your vegan buttermilk by adding 1 and ½ tablespoons of lemon juice to a measuring jug and adding soy milk (or almond milk) up to the 1 and ½ cup line (360ml). Leave it for a minute to curdle.
Prepare your flax egg by mixing 1 tablespoon of ground flaxseeds with 3 tablespoons of hot water from the kettle. Leave it for a minute to become gloopy.
Add the vegan buttermilk, flax egg, canola oil, vinegar and vanilla extract to the mixing bowl and mix into a batter. Don't over-mix.
Transfer the batter to your prepared 9x13 baking pan.
Bake for 25-30 minutes or until a toothpick inserted into the center of the cake comes out clean.
Let the cake cool completely before frosting.
Prepare your frosting by adding vegan butter, powdered sugar, cocoa powder, vanilla extract and 4 tablespoons of soy milk to the bowl of your stand mixer. Starting at slow speed, gradually increase the speed until the frosting is thick and smooth.
If your frosting is too thick, add the remaining 1 tablespoon of soy milk.
When the cake is completely cooled, frost it with the chocolate frosting and decorate with chocolate shavings.

Notes

Measure the flour correctly. The best way to measure your flour is to weigh it out on a food scale. If you don't have a food scale then the next best method is the 'spoon and level' method. Spoon the flour into your measuring cup and then level off the top with a knife.
Vegan buttermilk - I prefer soy milk for making vegan buttermilk as it creates a thicker/richer buttermilk but almond milk also works if you prefer to use that.
Flax egg - if you need a substitute for the flax egg, then you can use 3 tablespoons of applesauce instead.
Baking pan sizes. This recipe also works great in a 10x15 baking pan. You will just get a larger, thinner cake. Baking time will be 15-20 minutes (it's usually ready right around 17 minutes).
Make it gluten-free. For a gluten-free version switch the regular all purpose flour for a gluten free all purpose blend.
Storing and freezing: Keep it stored in an airtight container at room temperature for 2-3 days or in the fridge for up to a week. If you're storing it in the fridge, then let it come to room temperature before serving. You can freeze it for up to 3 months. Thaw it overnight in the fridge and bring to room temperature before serving.

Nutrition