Chocolate Chocolate Cake: The Most Deeply Fudgy Layer Cake You'll Ever Make

If you want a chocolate cake that actually tastes like chocolate, not just a brown-colored vanilla cake with cocoa dust, this is the one. This chocolate chocolate cake uses both natural cocoa and a shot of hot coffee in the batter to pull every bit of depth out of the chocolate, then layers it with a chocolate buttercream made with melted dark chocolate, not just cocoa powder. The result is dense, fudgy, and so rich that a small slice genuinely satisfies.

This is the cake I make for birthdays, for potlucks, and honestly sometimes just for a Tuesday when life calls for something worth eating. It takes a couple of hours from start to finish, but none of the steps are complicated. If you can stir batter and frost a cake, you can make this.

What Makes This Cake So Chocolatey

The double chocolate thing is not just a name. It means chocolate appears in both the cake layers and the frosting, and in each case, you are using more than one form of it.

For the cake, that means both Dutch-process cocoa (which gives a deep, smooth chocolate flavor) and a good amount of neutral oil to keep the crumb moist. The hot coffee is the other secret. You do not taste coffee in the finished cake, but caffeine amplifies cocoa flavor the same way salt amplifies sweetness. Swap in hot water if you prefer, and the cake will still be delicious, just a shade less intense.

For the frosting, melted bittersweet chocolate goes in alongside cocoa powder and butter. The melted chocolate gives the frosting a glossy, almost ganache-like quality that cocoa alone cannot achieve.

Ingredients You'll Need

For the cake layers:

2 cups all-purpose flour 2 cups granulated sugar 3/4 cup Dutch-process cocoa powder 2 teaspoons baking soda 1 teaspoon baking powder 1 teaspoon fine salt 2 large eggs, room temperature 1 cup buttermilk, room temperature 1 cup strong brewed coffee, hot 1/2 cup neutral oil (like avocado or vegetable) 1 teaspoon pure vanilla extract

For the chocolate buttercream:

4 oz bittersweet chocolate (70% or close), melted and cooled 1 cup (2 sticks) unsalted butter, softened 3 cups powdered sugar, sifted 1/4 cup Dutch-process cocoa powder 3 to 4 tablespoons heavy cream 1 teaspoon vanilla extract Pinch of salt

How to Make the Cake Layers

Preheat your oven to 350°F. Grease two 9-inch round cake pans, then line the bottoms with parchment paper and grease that too. Flouring the pans after greasing helps if your pans tend to stick.

Whisk together the flour, sugar, cocoa, baking soda, baking powder, and salt in a large bowl. In a separate bowl or large measuring cup, whisk the eggs, buttermilk, oil, and vanilla. Pour the wet ingredients into the dry and stir until just combined. Then slowly pour in the hot coffee while stirring. The batter will be thin. That is correct.

Divide the batter evenly between the two pans. They will look underfilled, but the layers rise nicely. Bake for 30 to 35 minutes, until a toothpick inserted in the center comes out with just a few moist crumbs. Do not overbake this one. The crumbs on the toothpick mean it is done.

Cool the layers in the pans for 15 minutes, then turn them out onto a wire rack to cool completely. Completely means completely. Frosting warm cake is how you end up with a melted mess.

How to Make the Chocolate Buttercream

Melt your chocolate gently, either in a double boiler or in 30-second microwave bursts, stirring between each. Set it aside to cool to room temperature while you start the butter.

Beat the softened butter with a hand mixer or stand mixer on medium-high for about 3 minutes, until it is pale and fluffy. Add the sifted powdered sugar one cup at a time, mixing on low after each addition so you do not end up wearing it. Add the cocoa powder and mix until combined.

Pour in the cooled melted chocolate, vanilla, and salt. Beat on medium until smooth. Add the heavy cream one tablespoon at a time until the frosting reaches a consistency that spreads easily without tearing the cake. Taste it. Adjust salt if needed.

Assembling and Frosting the Cake

Place one cake layer on your serving plate or a cake board. Spread about a cup of frosting across the top in an even layer. Set the second layer on top, flat side up (the flat bottom of the cake pan becomes your nice smooth top).

Apply a thin crumb coat of frosting all over the outside of the cake, then refrigerate for 20 minutes. This step sets the crumbs so your final layer of frosting goes on clean. After chilling, frost the outside with the remaining buttercream. You can go smooth with an offset spatula, or swipe it on in rustic swoops. Either looks intentional.

Let the assembled cake sit at room temperature for 30 minutes before slicing so the frosting softens slightly and the layers settle.

Tips for Getting It Right

Room temperature ingredients matter more than most baking recipes admit. Cold eggs and cold buttermilk do not incorporate as evenly, and you will notice it in the texture.

Do not skip sifting the cocoa powder for the buttercream. Cocoa clumps badly and will give you a grainy frosting if you dump it in unsifted.

This cake actually improves overnight. The layers get moister as the frosting keeps everything hydrated. If you can make it the day before you need it, store it covered at room temperature (not the fridge, which dries out cake), and it will be even better the next day.

Leftovers keep at room temperature under a cake dome for up to 3 days, or you can refrigerate individual slices wrapped tightly for up to a week.

Frequently Asked Questions