Chocolate Sheet Cake

If there’s one cake to rule them all, it’s the chocolate sheet cake. Rich, indulgent, and perfect for any gathering, it can hang out in the fridge for a couple of days before its big debut. Just remember to bring it to room temp and wield a plastic knife for cutting—unless you enjoy frosting clinging to your blade like it’s auditioning for a cake drama.

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Ingredients

For the Cake:
2 cups all-purpose flour
2 cups sugar
½ teaspoon baking soda
½ teaspoon salt
2 eggs (at room temperature)
2 egg yolks (at room temperature)
2 teaspoons vanilla extract
¼ cup sour cream
8 oz semi-sweet chocolate chips
½ stick unsalted butter
¾ cup vegetable oil
¾ cup water
½ cup Ghirardelli cocoa powder
For the Frosting:
1 stick unsalted butter
½ cup heavy cream
½ cup Dutch-process cocoa powder
1 tablespoon corn syrup
3 cups powdered sugar
1 tablespoon vanilla extract

Instructions

Step 1: Prep for Success
Preheat your oven to 350°F. This is where the magic starts.
Grease an 18″ x 13″ baking sheet like your life depends on it—no cake shall stick on your watch!
Step 2: Make the Cake Batter
In a large bowl, whisk together the flour, sugar, baking soda, and salt. These dry ingredients are the building blocks of greatness.
In another bowl, whisk the eggs, egg yolks, vanilla, and sour cream until smooth. Think of it as a little workout before the chocolate indulgence.
Heat the chocolate chips, butter, vegetable oil, cocoa powder, and water in a large saucepan over medium heat. Stir occasionally until the mixture is smoother than a pickup line at a dessert bar (3-5 minutes).
Gradually whisk the melted chocolate mixture into the dry ingredients. Take your time—this is chocolate we’re talking about.
Finally, whisk the egg mixture into the batter. You’ve just created liquid gold. Pour it into the baking sheet.
Step 3: Bake the Cake
Bake for 18-20 minutes or until a toothpick inserted into the center comes out clean. This is the moment of truth!
Transfer the cake to a wire rack and let it cool slightly while you prepare the frosting.
Step 4: Make the Frosting
In a large saucepan, heat the butter, heavy cream, cocoa powder, and corn syrup over medium heat, stirring occasionally, until the mixture is as smooth as your cake batter (about 3-5 minutes).
Remove the pan from the heat and whisk in the powdered sugar and vanilla. The frosting should be silky, shiny, and irresistible.
Step 5: Frost and Finish
Spread the warm frosting evenly over the hot cake—don’t skimp! If you’re feeling fancy, sprinkle pecans over the top, or wait until it cools and crown each square with a red raspberry.
Let the cake cool to room temperature, then refrigerate until the frosting sets. This cake is patient; it knows the best things come to those who wait.

Notes

Use a plastic knife to cut the cake—it’s the secret weapon against sticky frosting drama.
This cake tastes even better the next day, so don’t be shy about making it ahead of time.
If you’re serving this at a party, watch out—guests might not leave until they get seconds!

This chocolate sheet cake is simple to make, hard to resist, and guaranteed to turn any occasion into a celebration. Whether you top it with pecans or raspberries, you’re in for a sweet treat!