Easy One-Layer Chocolate Afternoon Cake

Why I Love Single Layer Cakes

Over the past year or so I have found myself gravitating towards single layer cakes (vs the traditional double). Don’t get me wrong, I do like a towering layer cake in all its glory (for instance, my favorite birthday cake or this chocolate cake with espresso buttercream), but the single layer cake feels very different: it doesn’t need fancy piping or flowers to grace a table, it’s much easier to eat, and there is a better frosting to cake ratio.

You can also put it out in the afternoon and it is perfectly acceptable. Instead of hearing, “why did you make a giant birthday cake on a Tuesday afternoon for no reason?” friends and family will say, “Oh! A little piece of this afternoon snacking cake is just what I needed after this very long day.” (If you need a similar snacking cake for a crowd, I have my Minnesota Chocolate Sheet Cake, too.)

What Makes This Cake so Fudgy & Moist

This particular cake is inspired by several other chocolate cake recipes I make. All the usual cake ingredient suspects are there: sugar, flour, eggs, cocoa powder, vanilla, and oil, but what makes this recipe unique is at the end of mixing, hot coffee is added to the bowl. 

As the coffee is gently stirred in, the batter turns into an unpromising dark sludge, but bakes up into a moist, delicious cake. Different coffee roasts can add a slightly different flavor to the cake, and over the years I’ve found I love Peace Coffee’s Tree Hugger blend. However, your favorite roast will work well.

And, instead of my regular chocolate buttercream, I have a fudgy creme fraiche buttercream. There is no messy melted chocolate to deal with, as the frosting uses cocoa powder instead. I love Guittard’s Cocoa Rogue Dutch cocoa powder in both the cake base the the buttercream, and have been using that when I can in my baking. It can be hard to find; otherwise I use Rodelle Gourmet Baking Cocoa Powder.

Moist, Fudgy One-Layer Chocolate Cake

Servings: 8 pieces

Prep Time: 20 minutes minutes

Cook Time: 25 minutes minutes

This single-layer chocolate cake has the best dense, moist, and rich chocolate crumb! Chocolate buttercream adds a luscious finish that complements the cake's deep flavor. It's the perfect snacking cake, no special occasion needed.

Sarah Kieffer

4.41 from 5 votes

Print Pin Rate

Ingredients

Chocolate cake

• 1/2 cup [100 g] granulated sugar
• 1/2 cup [100 g] brown sugar
• 1/2 cup [120 g] crème fraîche, at room temperature
• 1/3 cup [33 g] Dutch-process cocoa powder
• 1/4 cup [56 g] vegetable or canola oil
• 1 large egg, at room temperature
• 2 large egg yolks, at room temperature
• 1/2 teaspoon baking powder
• 1/2 teaspoon baking soda
• 1 teaspoon vanilla extract
• 1 teaspoon fine salt
• 1 cup minus 2 tablespoons [125 g] all-purpose flour*
• 1/3 cup [80 g] strong, freshly brewed coffee, hot

Crème fraîche chocolate buttercream

• 1/2 cup [8 tablespoons or 113 g] unsalted butter, at room temperature
• 1/3 cup [33 g] Dutch-process cocoa powder
• 1 tablespoon corn syrup
• 1 teaspoon pure vanilla extract
• Pinch salt
• 1/2 cup [120 g] crème fraîche
• 1 1/2 cup [180 g] confectioners' sugar
• 1 tablespoon water, at room temperature

Instructions

For the cake

• Position an oven rack in the middle of the oven and preheat the oven to 350F [180C]. Grease an 8 in [20 cm] baking pan and line the bottom with parchment paper.
• In a large bowl, whisk together the granulated and brown sugars, cocoa powder, oil, crème fraîche, egg, yolks, baking soda, baking powder, vanilla, and salt until well combined. Add the flour and use a spatula to stir until just combined. Slowly pour the coffee into the batter and mix until just combined.
• Pour the batter into the prepared pan. Tap the pan on the counter a few times to remove any air bubbles.
• Bake for 24 to 30 minutes, rotating the pan halfway through, until a wooden skewer or toothpick inserted into the center comes out with the tiniest bit of crumb. Transfer the pan to a wire rack and let cool for 20 minutes. Turn the cake out onto the rack, remove the parchment paper, and let cool completely. Top the cake evenly with the buttercream, the slice and serve. Store the cake in the refrigerator, covered, for up to 2 days.
• For the buttercream
• In the bowl of a stand mixer fitted with a paddle, beat the butter on medium speed for 2 to 3 minutes, until creamy. Add the cocoa powder, corn syrup, vanilla, and salt and mix again on medium speed for 2 to 3 minutes, until light and creamy. Scrape down the sides of the bowl, add the crème fraîche, and mix on low speed until combined. Add the confectioners' sugar and mix on low speed until combined, then add the tablespoon of water and mix again on low for 1 to 2 minutes, until combined and creamy The more you mix, the lighter the frosting will get. Finish mixing with a spatula, making sure all the ingredients are evenly incorporated.

Notes

Throughout my recipes posted on this website, 1 cup of flour equals 142g. Please note that 1 cup of flour can range anywhere from 120g to 142g, depending on the baker or website. I found that after weighting many cups of flour and averaging the total, mine always ended up around this number. If I am posting a recipe from another cookbook, I will use whatever gram measure of flour used in that book, which is why you may see a few posts with a different cup measurement.

Different brands of flour have varying levels of protein, ranging from low to high, which can result in very different outcomes when baking. I’ve found Gold Medal all-purpose unbleached flour to be the best option for many of my recipes; I use it in all the baked goods that don’t use yeast.