Chocolate Sheet Cake
A deliciously moist and fluffy chocolate cake spiced with cinnamon and topped with chocolate buttercream frosting!
Servings: 16 slices
Ingredients
For the Cake
- 2 cups (250g) cake flour*
- ½ cup (50g) cocoa powder
- 1 teaspoon baking soda
- ½ teaspoon baking powder
- ½ teaspoon salt
- 2 teaspoons ground cinnamon
- 3 large eggs room temperature
- 1 ¼ cups (250g) light brown sugar
- 2 teaspoons vanilla extract
- ½ cup (115g) unsalted butter melted
- ¾ cup (180g) Greek yoghurt
For the Frosting
- 4 cups (500g) icing/powdered sugar
- 1 cup (226g) unsalted butter softened
- ½ cup (50g) cocoa powder
- 3 - 4 tablespoons milk
- 1 teaspoon vanilla extract
Instructions
For the Cake
- Preheat the oven to 180C/350F/Gas 4. Grease a 13x9-inch pan, and set aside.
- Whisk together the flour, cocoa powder, baking powder, baking soda, salt, and cinnamon. Set aside.
- Whisk together the eggs. Add the sugar, and whisk until combined. Add the vanilla extract, butter, and yoghurt and whisk until combined. Gradually fold in the dry ingredients.
- Pour the batter into the prepared pan, and spread out evenly. Bake for 18 - 20 minutes, or until a toothpick inserted into the centre comes out clean.
- Allow to cool completely in the pan on a wire rack.
For the Frosting
- Using a handheld or stand mixer, beat together the butter and icing sugar until light and fluffy. Beat in the cocoa powder, milk and vanilla until smooth, and spreadable. Add more milk if needed.
- Spread the frosting evenly over the cooled cake (leaving about 1/2 - 1 cup for piping). Transfer the remaining frosting to a piping bag and pipe swirls on each slice of cake. Garnish with sprinkles.
Notes
*Make your own cake flour! Measure out 2 cups (250g) of plain/all-purpose flour, remove 4 tablespoons, and replace with 4 tablespoons of cornflour/cornstarch. Sift well.
Leftovers can be stored, covered, in the fridge for up to 2 - 3 days.
After the cake has cooled completely, it can be wrapped in clingfilm and refrigerated/frozen overnight, ready to be frosted the next day. The frosting can also be refrigerated overnight.
Frosted or unfrosted cake freezes well for up to 2 months.