Hostess Sheet Cake Recipe
The hostess sheet cake recipe offers a rich, indulgent chocolate flavor that feels moist and tender. The cake has a soft, delicate crumb that melts in the mouth, while the marshmallow buttercream filling adds a light, airy sweetness that contrasts beautifully with the chocolate.The ganache on top is smooth, creamy, and slightly bittersweet, enhancing the chocolate depth. Subtle hints of espresso highlight the richness of the cocoa.
Equipment
- Mixing bowls
- Whisk and/or electric mixer
- 9×13-inch baking pan (or similar size)
- Measuring cups and spoons
- Spatula
- Saucepan
- Heatproof bowl (for ganache)
- Cooling rack
Ingredients
For the Cake:
- 250 g all-purpose flour 2 cups
- 400 g sugar 2 cups
- 2 large eggs
- 75 g unsweetened cocoa powder 3/4 cup
- 10 g baking powder 2 teaspoons
- 10 ml vanilla extract 2 teaspoons
- 240 ml boiling water 1 cup
- 7.5 g baking soda 1 1/2 teaspoons
- 120 ml vegetable canola, or melted coconut oil (1/2 cup)
- 1 teaspoon espresso powder homemade or store-bought
- 240 ml milk buttermilk, almond, or coconut milk (1 cup)
- 5 g kosher salt 1 teaspoon
For the Creamy Filling:
- 115 g softened butter
- 200 g powdered sugar
- 125 g marshmallow fluff or marshmallow cream
- 5 ml vanilla extract 1 teaspoon
- 60 ml heavy cream 1/4 cup, more if needed
For the Ganache:
- 2 bars 4 oz each / 225 g total quality semi-sweet chocolate
- 240 ml heavy cream 1 cup
Instructions
- Start by heating the oven to 175°C (350°F). Lightly grease a 9×13-inch baking pan and dust it with a little flour so the cake doesn’t stick. Sift together the flour, cocoa powder, baking powder, baking soda, espresso powder, and salt in a large bowl.
- In another bowl, whisk sugar, eggs, oil, vanilla, and milk until smooth and combined. Pour the dry ingredients into the wet ingredients slowly, stirring gently to combine.
- Bring some water to a boil and pour it into the batter carefully, mixing as you go. The batter will look very thin, but that’s exactly what makes the cake moist.
- Transfer the batter into the prepared pan and place it in the oven. Bake for 30–35 minutes. Check if it’s done by inserting a toothpick in the center; it should come out clean. Let the cake cool completely before moving on.
- To make the filling, beat softened butter until smooth. Add powdered sugar gradually, then mix in marshmallow fluff and vanilla. Pour in heavy cream slowly until the filling is light and easy to spread.
- For the ganache, heat heavy cream in a small saucepan just until it starts to simmer. Pour it over chopped chocolate in a heatproof bowl. Let it sit for 2–3 minutes, then stir until the mixture is glossy and smooth.
- Once the cake has cooled, slice it in half horizontally if you want two layers. Spread the filling evenly on the bottom layer and place the top layer back on.
- Pour the ganache over the cake, spreading it evenly. Let it rest for a bit so the ganache sets, then cut and serve.