Chocolate Sheet Cake Recipe
This Chocolate Sheet Cake Recipe offers a rich, moist cake topped with creamy chocolate buttercream. Made with basic ingredients like cocoa, buttermilk, and vegetable oil, it’s easy to prepare and bakes in a single layer. Adding hot water or coffee boosts the chocolate flavor. This simple yet indulgent dessert is perfect for gatherings and quick baking sessions, delivering classic chocolate goodness every time.
Equipment
- 9×13 inch baking pan
- Mixing bowls (one large, one medium)
- Electric mixer or hand whisk
- Measuring cups and spoons
- Rubber spatula
- Wire cooling rack
- Offset spatula or butter knife
- Sifter (optional, for cocoa and sugar)
Ingredients
For the Chocolate Sheet Cake:
- 2 cups 250g all-purpose flour
- 2 cups 400g granulated sugar
- ¼ cup 25g cocoa powder (heaping)
- 1 tsp baking soda
- ½ tsp salt
- 1 cup 240ml vegetable oil
- 2 large eggs
- 1 cup 240ml buttermilk (or substitute: 1 cup milk + 1 tbsp vinegar or lemon juice)
- 1 tsp vanilla extract
- 1 cup 240ml hot water or hot coffee (coffee enhances the chocolate flavor)
For the Chocolate Buttercream:
- 1½ cups 339g unsalted butter, at room temperature
- ¾ cup 68g cocoa powder (heaping)
- 4 tbsp whole milk room temperature
- 4 cups 480g powdered sugar
- 1 tbsp pure vanilla extract
- Pinch of salt to taste
Instructions
Preheat Your Oven:
- Set your oven to 350°F (175°C). Grease and flour a 9×13-inch baking pan, or line it with parchment paper for easy removal.
Mix the Dry Ingredients:
- In a large mixing bowl, whisk together the flour, sugar, cocoa powder, baking soda, and salt. Make sure everything is evenly combined and there are no lumps of cocoa.
Add the Wet Ingredients (Except Hot Liquid):
- Add the vegetable oil, eggs, buttermilk (or the milk + vinegar substitute), and vanilla extract to the dry ingredients. Mix until everything is just combined. Don’t overmix.
Pour in the Hot Water or Coffee:
- Slowly stir in the hot water or hot coffee. The batter will be thin, but that’s exactly what you want for a moist cake. Stir gently until smooth.
Bake the Cake:
- Pour the batter into the prepared pan. Bake for 28–32 minutes, or until a toothpick inserted in the center comes out clean. Once baked, place on a wire rack and let the cake cool completely in the pan.
Prepare the Chocolate Buttercream:
- In a large bowl, beat the softened butter on medium-high speed for 2–3 minutes until creamy and pale. Sift in the cocoa powder and powdered sugar, add the milk, vanilla, and a pinch of salt.
Whip the Frosting Until Fluffy:
- Beat everything together on low speed to avoid sugar clouds, then switch to high speed and whip for 2–3 minutes until the frosting is light, fluffy, and smooth. Adjust consistency with more milk if too thick, or more powdered sugar if too loose.
Frost the Cake:
- Once the cake has cooled completely, spread the chocolate buttercream evenly over the top using a spatula or butter knife. Get the edges clean and smooth it out to your preference.
Serve or Store:
- Slice into squares and serve. If not serving immediately, cover and store at room temperature for up to 2 days, or refrigerate for up to 5 days. Bring to room temp before serving for best texture.
Notes
If you want to add a touch of flair, consider incorporating a swirl of caramel sauce or a sprinkle of sea salt on top of the frosting.
For a festive twist, you can use colored sprinkles or edible glitter to decorate the cake. This chocolate sheet cake also pairs wonderfully with a scoop of vanilla ice cream, making it a perfect dessert for a casual family dinner or a lively party.