Name: Chocolate Blackout Sheet Cake with Chocolate Cookie Crumbs
Prep time: 20 min
Cook time: 35 min
Total time: 55 min
Ingredients: 1 cup all-purpose flour; 65 g Dutch-process cocoa powder (sifted); 100 g granulated sugar; 1 teaspoon cornstarch; 1 teaspoon kosher salt; 6 tablespoons unsalted butter (melted); 1 ½ cups all-purpose flour; 75 g Dutch-process cocoa powder (sifted); 2 teaspoons baking soda; 1 teaspoon baking powder; 1 teaspoon kosher salt; 1 ½ cups granulated sugar; 1 cup low-fat buttermilk; ¾ cup vegetable oil; 2 large eggs (at room temperature); 2 teaspoons vanilla extract; 1 cup heavy cream; 3 tablespoons unsalted butter (cut into chunks); 100 g granulated sugar; 2 tablespoons light corn syrup (or golden syrup); 1 teaspoon vanilla extract; 60 g dark chocolate chips (or chopped dark chocolate); 50 g Dutch-process cocoa powder (sifted); 1 pinch salt; Sprinkles

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There’s something undeniably satisfying about a rich, chocolatey cake that hugs you like a warm blanket. This Chocolate Blackout Sheet Cake with Chocolate Cookie Crumbs is not just any cake; it’s a chocolate lover’s dream come true! With layers of deep, dark chocolate and a delightful crunch from chocolate cookie crumbs, this cake is perfect for any occasion—birthdays, holidays, or simply a Tuesday that needs a little sweetness.

Imagine layers of moist chocolate cake topped with a velvety chocolate ganache and finished with a sprinkle of cookie crumbs. The combination of textures and flavors makes each bite a celebration. So, let’s get right to it!

Why This Recipe is a Keeper

This Chocolate Blackout Sheet Cake with Chocolate Cookie Crumbs is a showstopper for many reasons. Here are just a few:

Decadent Flavor: The intense chocolate flavor is balanced perfectly with the creamy ganache.
Easy to Make: The sheet cake format is simple, making it perfect for bakers of all skill levels.
Perfect for Sharing: This recipe yields a generous amount—ideal for gatherings and parties.
Customizable: You can add your favorite toppings or adapt it for different occasions.

Ingredient Rundown

To make this delightful cake, you’ll need the following ingredients:

Chocolate Cookie Crumbs:
- 1 cup (85g) all-purpose flour
- 65g Dutch-process cocoa powder, sifted
- 100g granulated sugar
- 1 teaspoon cornstarch
- 1 teaspoon kosher salt
- 6 tablespoons (84g) unsalted butter, melted
Chocolate Cake:
- 1 ½ cups (160g) all-purpose flour
- 75g Dutch-process cocoa powder, sifted
- 2 teaspoons baking soda
- 1 teaspoon baking powder
- 1 teaspoon kosher salt
- 1 ½ cups (300g) granulated sugar
- 1 cup (280g) low-fat buttermilk
- ¾ cup (72g) vegetable oil
- 2 large eggs, at room temperature
- 2 teaspoons vanilla extract
Chocolate Ganache:
- 1 cup (240g) heavy cream
- 3 tablespoons unsalted butter, cut into chunks
- 100g granulated sugar
- 2 tablespoons (44g) light corn syrup or golden syrup
- 1 teaspoon vanilla extract
- 60g dark chocolate chips or chopped dark chocolate
- 50g Dutch-process cocoa powder, sifted
- Pinch of salt
Optional Decoration:
- Sprinkles

Before You Start: Equipment

Before diving into the recipe, gather the following equipment to streamline your baking process:

Mixing Bowls: A set of various sizes for mixing dry and wet ingredients.
Whisk: For combining ingredients smoothly.
Rubber Spatula: For scraping down the sides of the bowl and folding in ingredients.
9×13 inch Baking Pan: The ideal size for sheet cakes.
Cooling Rack: To cool the cake properly before frosting.
Double Boiler or Microwave-Safe Bowl: For melting chocolate for the ganache.

Directions: Chocolate Blackout Sheet Cake with Chocolate Cookie Crumbs

Step 1: Preheat the Oven

Preheat your oven to 350°F (175°C). Grease and flour a 9×13 inch baking pan to ensure your cake releases easily after baking.

Step 2: Make the Chocolate Cookie Crumbs

In a mixing bowl, combine 1 cup of all-purpose flour, 65g of sifted Dutch-process cocoa powder, 100g of granulated sugar, 1 teaspoon of cornstarch, and 1 teaspoon of kosher salt. Mix well. Pour in 6 tablespoons of melted unsalted butter and stir until the mixture resembles wet sand. Set aside.

Step 3: Prepare the Chocolate Cake Batter

In another large mixing bowl, whisk together 1 ½ cups of all-purpose flour, 75g of sifted Dutch-process cocoa powder, 2 teaspoons of baking soda, 1 teaspoon of baking powder, and 1 teaspoon of kosher salt. In a separate bowl, mix 1 ½ cups of granulated sugar, 1 cup of low-fat buttermilk, ¾ cup of vegetable oil, 2 large eggs, and 2 teaspoons of vanilla extract until smooth. Gradually add the wet ingredients to the dry ingredients, mixing until just combined.

Step 4: Assemble the Cake

Pour half of the chocolate cake batter into the prepared baking pan. Sprinkle half of the chocolate cookie crumb mixture over the batter, then add the remaining batter on top. Finish by sprinkling the rest of the cookie crumbs over the top layer.

Step 5: Bake the Cake

Bake in the preheated oven for 30-35 minutes or until a toothpick inserted in the center comes out clean. Let the cake cool in the pan for about 10 minutes, then transfer it to a wire rack to cool completely.

Step 6: Make the Ganache

In a double boiler or microwave-safe bowl, heat 1 cup of heavy cream until just simmering. Remove from heat and add 3 tablespoons of unsalted butter, 100g of granulated sugar, 2 tablespoons of light corn syrup, and 1 teaspoon of vanilla extract. Whisk until the butter melts and the mixture is smooth. Stir in 60g of dark chocolate until melted and combined, then sift in 50g of Dutch-process cocoa powder and a pinch of salt. Mix until smooth.

Step 7: Frost the Cake

Once the cake has cooled completely, pour the chocolate ganache over the top, allowing it to drip down the sides. Use an offset spatula to spread it evenly across the surface.

Step 8: Add Finishing Touches

If desired, sprinkle with colorful sprinkles for a festive touch.

Seasonal Adaptations

This Chocolate Blackout Sheet Cake with Chocolate Cookie Crumbs is versatile and can be adapted for different seasons and celebrations:

Add peppermint extract and crushed candy canes for a festive holiday twist.
Incorporate seasonal fruits, like raspberries or strawberries, for a fruity contrast.
Use different flavored extracts, such as almond or orange, for a unique flavor profile.
Top with whipped cream and chocolate shavings for an elegant presentation during special occasions.

If You’re Curious

Wondering about some of the science behind this cake? Here are some insights:

Why Dutch-process cocoa? Dutch-process cocoa gives a smoother, richer flavor compared to natural cocoa powder. It also reacts differently with baking soda, resulting in a lighter cake.
What does cornstarch do? Cornstarch helps create a tender crumb in the cookie crumbs, making them melt in your mouth.
Can I use different oils? While vegetable oil is commonly used, you can substitute with canola oil or even melted coconut oil for a different flavor.
How do I know when my cake is done? Insert a toothpick in the center; if it comes out clean or with a few moist crumbs, your cake is ready!

Freezer-Friendly Notes

This Chocolate Blackout Sheet Cake with Chocolate Cookie Crumbs is great for making ahead of time! Here’s how to do it:

Allow the cake to cool completely before wrapping it tightly in plastic wrap.
Store in an airtight container or resealable freezer bag to prevent freezer burn.
It can be frozen for up to 3 months. Thaw in the fridge overnight before serving.

Ask the Chef

Can I use gluten-free flour for this cake?

Absolutely! Substitute the all-purpose flour with a 1:1 gluten-free baking blend, and you’ll still achieve a delicious cake.

What can I use instead of buttermilk?

If you don’t have buttermilk on hand, you can make a quick substitute by mixing 1 cup of milk with 1 tablespoon of lemon juice or vinegar. Let it sit for 5 minutes before using.

How can I make this cake less sweet?

To reduce the sweetness, you can cut back on the sugar in the cake batter or ganache. You could also add a pinch of sea salt to balance the flavors.

What’s the best way to store leftovers?

Store any leftover cake in an airtight container at room temperature for up to 3 days. If you need to keep it longer, refrigerate it for up to a week.

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Wrap-Up

This Chocolate Blackout Sheet Cake with Chocolate Cookie Crumbs is a must-try for anyone who loves chocolate. Its rich flavor, combined with the crunch of cookie crumbs, makes it a delightful treat for any occasion. Whether you’re celebrating a special event or simply indulging in a sweet moment, this cake will surely impress your family and friends.

So, gather your ingredients, get your baking tools ready, and let the chocolate magic begin! Happy baking!