Decadent Chocolate Sheet Cake

This chocolate sheet cake is my secret weapon for potlucks and family gatherings, delivering deep chocolate flavor with minimal effort and maximum impact. The glossy ganache creates that wow factor while the coffee-infused cake stays impossibly moist for days.

I first made this cake when hosting an impromptu dinner party with zero time to prepare. The ease of whisking everything in one bowl and the consistently rave reviews have made this my go-to chocolate cake recipe for over a decade now.

• Brewed coffee: Amplifies the chocolate flavor without adding coffee taste perfect for using up morning leftovers
• Vegetable oil: Instead of butter creates exceptional moisture that lasts for days
• Apple cider vinegar: Activates the baking soda for the perfect rise and tender crumb
• Cocoa powder: Use a highquality brand like Ghirardelli for best flavor depth
• Heavy cream: For the ganache must be full fat for proper setting
• Corn syrup: Gives the ganache that professional glossy finish and smooth texture
• Chocolate for ganache: Choose semisweet chocolate bars rather than chips for smoother melting

Step-by-Step Instructions

Prepare Your Workspace:

Preheat your oven to 350°F and thoroughly spray a 9x13 pan with baking spray making sure to get into the corners. Gather all ingredients and measure them before beginning to ensure a smooth process.

Create The Base:

In a large bowl whisk together sugar coffee oil cocoa powder vinegar vanilla and salt until completely smooth. Take your time here to ensure the cocoa powder fully incorporates without dry pockets.

Develop The Structure:

Add the baking soda and whisk vigorously for about 30 seconds. The batter will begin to react immediately. Then gradually add the flour while continuing to whisk until you achieve a thin lumpfree batter. The consistency should be pourable similar to a thick hot chocolate.

Bake To Perfection:

Pour the batter into your prepared pan and sharply tap the pan on the counter 2-3 times to release air bubbles. Bake for exactly 30 minutes the cake bakes quickly due to its thinner profile. The center should feel firm but springy to the touch.

Create Luxurious Ganache:

After cooling the cake for at least 30 minutes place finely chopped chocolate in a heatproof bowl. Heat cream and corn syrup until small bubbles form around the edges then pour over chocolate. Let sit undisturbed for 3 minutes before stirring gently from the center outward until silky smooth.

Finish With Finesse:

Pour warm ganache over the cake starting from the center and working outward. Use an offset spatula to guide it to the edges and create a smooth finish. Allow to set at room temperature for about 2 hours before slicing with a warm knife for clean cuts.

The secret weapon in this recipe is definitely the brewed coffee. I discovered this trick when I accidentally used the last of my milk and had to improvise. My family immediately noticed the deeper chocolate flavor and now I always keep some coffee reserved just for baking chocolate desserts.

Storage Tips

This cake maintains its moisture exceptionally well due to the oil base. Store it covered at room temperature for up to 4 days or refrigerate for up to a week. If refrigerating bring slices back to room temperature before serving for best flavor and texture. The ganache will firm up in the refrigerator creating a different but equally delightful texture experience.

Make It Your Own

Feel free to customize this versatile base recipe. Add a teaspoon of cinnamon or espresso powder to the batter for warmth or coffee enhancement. For a minty twist add 1/4 teaspoon peppermint extract to the ganache. You can also transform it into a birthday cake by adding colorful sprinkles over the wet ganache or even substitute buttercream frosting if preferred by younger palates.

Perfect Pairings

This rich cake partners beautifully with contrasting accompaniments. Serve with fresh raspberries or strawberries to cut through the richness with bright acidity. A scoop of vanilla ice cream creates a hot and cold experience when the cake is served slightly warm. For adult gatherings pair with port wine or a good bourbon for an indulgent dessert experience.

Frequently Asked Questions

→ How do I ensure my cake stays moist?

Use brewed coffee and vegetable oil to add moisture to the batter. Be careful not to over bake, as this can dry out the cake. Check with a toothpick to ensure moist crumbs cling to it.

→ Can I substitute brewed coffee?

Yes, you can substitute with hot water or even milk if you prefer. However, coffee enhances the chocolate flavor without adding coffee taste.

→ How do I properly make ganache?

Scald heavy cream and corn syrup, then pour over chopped chocolate. Let the mixture sit for a few minutes, then stir until smooth and glossy. Add vanilla for extra flavor.

→ What’s the best way to store leftovers?

Store leftover cake covered at room temperature for a day or refrigerate for up to 4-5 days. Bring it to room temperature before serving for the best texture.

→ Can I make this cake ahead of time?

Yes, you can bake the cake in advance and store it. Add the ganache topping just before serving for a fresh finish.