This ultimate chocolate fudge cake has it all! Dark chocolate cake layers, chocolate ganache and fudge buttercream frosting.

chocolate fudge layer cake on a cake stand

This is the chocolate cake to end all chocolate cakes! And it’s every chocolate lover’s dream come true.

It’s a combination of a few of my favorite recipes— my chocolate sour cream cake layers (aka the best chocolate cake ever), my easy fudge buttercream frosting, and classic chocolate ganache to take the whole thing to the next level.

This chocolate fudge cake is moist, rich and indulgent. It’s special without being overly difficult or fussy, and it’s the perfect dessert for any occasion, big or small.

slice of chocolate fudge cake on a plate

Three layers of chocolate

There are 3 delicious components to this cake:

  1. Dark chocolate cake layers.
  2. Chocolate ganache.
  3. Fudge buttercream frosting.

Layer cakes are a labor of love, it’s true. And while this is far from the most complicated cake I’ve shared on the blog, it does require some time and commitment. But like all beautiful and delicious cakes, it will be worth it in the end!

So let’s bake a cake, shall we?

dark chocolate cake layers

Bake the chocolate cake layers

Starting off with my chocolate sour cream cake layers means this cake has a tender, moist texture and excellent flavor. You can use any kind of natural unsweetened cocoa powder (not dutch-processed), but I like to use Hershey’s Special Dark cocoa powder in this recipe for even more chocolate flavor (it’s actually a blend of natural and dutch-processed cocoa powder so it will work in this recipe).

Adding coffee to the batter enhances the chocolate flavor and doesn’t give the cake a coffee flavor at all. If baking with coffee is out of your norm, keep a jar of instant espresso or coffee granules in your pantry for recipes such as these.

The chocolate cake batter is almost a one-bowl recipe and doesn’t require an electric mixer. Simply combine all of the dry ingredients in one bowl, and all of the liquid ingredients in another bowl, and then combine everything together. Once the cake layers are baked, let them cool while you prepare the ganache and buttercream.

chocolate ganache in a bowl

Make the ganache

Ganache is the easiest way to elevate any cake! It requires just 2 ingredients and 5 minutes to make. Pour heated heavy cream over chocolate pieces and let it sit for several minutes, then stir until smooth. If a few lumps of chocolate remain, microwave it in 15-second bursts until smooth.

I typically use dark or bittersweet chocolate, but semi-sweet will work too. You can use a chopped chocolate bar or chocolate chips, but note that higher quality chocolate will make for a silkier, better-tasting ganache.

easy fudge frosting in mixing bowl

Make the easy fudge buttercream frosting

This easy fudge buttercream has been my go-to chocolate frosting for years. The “fudgy” quality comes from the fact that it’s made in the food processor. It blends the frosting ingredients in just a few seconds without incorporating much air, so the buttercream is dense and chocolate-y but also soft and creamy.

It is possible to make this frosting with an electric mixer, though it will take several minutes longer and it will have a fluffier consistency and lighter color.

assembling chocolate fudge layer cake

Choose your number of cake layers

Layer cakes like this have a sort of “choose-your-own adventure” component based on 1) how many layers you want, 2) how tall you want the cake to be, 3) the ratio of cake to frosting, and 4) what cake pans you have.

I baked this cake in two 8×3-inch round cake pans, and then cut each layer in half, to make 4 layers total. I love the combination of thinner (1-inch) cake layers with the frosting and ganache, but you can do it differently per your preference. Here are a few things to remember:

  • 8-inchcake pans will yield a taller cake, while 9-inch cake pans will yield a wider, shorter cake.
  • This cake will be delicious and beautiful with 2, 3 or 4 layers. There is no one right way, and you don’t have to do 4 layers just because that’s what you see here.
  • Never fill cake pans more than 2/3 full, or they may overflow in the oven (if your 8-inch cake pans aren’t 3 inches deep you won’t be able to bake 2 layers like I did).
  • To make sure each layer is equal in size, use a digital kitchen scale and add equal batter amounts to each pan.
  • Check out my tutorial for how to split a single cake layer into two.
closeup of chocolate fudge cake on cake stand

How to assemble this chocolate fudge cake

Once your cake layers are baked and cooled, and the frosting and ganache are ready, you are ready to assemble the cake!

  1. Add one cake layer to a plate or cake stand.
  2. Top with about 1 cup of frosting and spread it into an even layer.
  3. Top with 1/2 cup of ganache. (These amounts are for a 4-layer cake. If you are doing less layers you can be more generous with your filling amounts).
  4. Top with the next cake layer and repeat until you’ve added the top layer.
  5. Frost the cake with the remaining fudge buttercream.
  6. Add chocolate ganache to the top, letting it drip down the sides as desired. If you want to create a nice drip like in these photos, rewarm the ganache to thin it out, and/or add 1 tablespoon heavy cream. Use a spoon to gently encourage drips over the edge. (This video is a great tutorial!)

If you’re new to baking layer cakes or need a little help, be sure to check out my complete guide for how to build a layer cake. It’s got everything you need to know!

A few more cake baking tips

  • For the absolute best results, have the sour cream and eggs at room temperature before mixing the cake. This will help the ingredients combine better, which affects rise and texture.
  • Do your cakes tend to stick to the inside of the pan? See how I prepare my cake pans so they come out clean every single time.
  • If you need a little help frosting your cake like a (semi) pro, see my full tutorial.
  • Chilling the cake in the fridge for 30-60 minutes before serving will firm up the frosting and cake layers for clean slices.
  • The unassembled cake layers store very well. Wrap cake layers in plastic wrap and store in the fridge for up to 3 days or in the freezer (double wrapped) for several months. Thaw in the fridge overnight before assembling. For best results, I prefer to make the frosting and ganache, and assemble the cake when I’m ready to serve.
slice of chocolate fudge cake on a plate with cake in background

More chocolate cakes to love

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This recipe was originally published April 2015.

closeup of chocolate fudge cake on cake stand
4.50 from 2 reviews

Chocolate Fudge Layer Cake

Servings: 12 slices
Prep Time: 30 minutes
Cook Time: 25 minutes
Assembly Time: 1 hour
Total Time: 1 hour 55 minutes
This ultimate chocolate fudge cake has it all! Dark chocolate cake layers, chocolate ganache and fudge buttercream frosting.

Ingredients
 

For the chocolate cake:

  • 2 ½ cup all-purpose flour (300 grams)
  • 1 cup unsweetened cocoa powder (110 grams)
  • 2 ½ teaspoon baking soda
  • 1 teaspoon salt
  • 2 cups granulated sugar (400 grams)
  • 3 large eggs
  • 1 ¼ cups sour cream (280 grams)
  • 1 cup vegetable oil (198 grams)
  • 1 ¼ cup coffee (284 grams)

For the fudge frosting:

  • 6 oz unsweetened or dark chocolate , melted and cooled (170 grams)
  • 4 ½ cups powdered sugar (563 grams)
  • 1 ½ cups unsalted butter , at room temperature (340 grams)
  • 6 tablespoons whole milk or half and half (85 grams)
  • 1 tablespoon vanilla extract

For the ganache:

  • 6 oz dark, bittersweet or semi-sweet chocolate (170 grams)
  • ¾ cup heavy cream (170 grams)

Instructions
 

To make the chocolate cake layers:

  • To make the cake, preheat oven to 350°F. Butter and flour two or three 8-inch or 9-inch cake pans (see Notes) and line bottoms with parchment paper.
  • In a large bowl, sift together the flour, sugar, cocoa powder, salt, and baking soda.
  • In another bowl, whisk together eggs, sour cream, and vegetable oil. Add coffee and whisk until smooth.
  • Add wet ingredients all at once to the dry ingredients and whisk until no streaks of dry ingredients remain. Do not overmix.
  • Divide the batter evenly between the prepared cake pans and bake until a toothpick inserted into the center comes out clean, about 25-35 minutes (see Notes). Let cool in the pan for 10 minutes, then remove and place on a wire rack to cool completely.

To make the chocolate ganache:

  • Add chocolate to a microwave-safe bowl. Heat heavy cream until steaming and then pour over the chocolate. Let it sit for 5 minutes, then stir until smooth.
  • If a few lumps of chocolate remain, heat in the microwave in 15-second bursts, stirring in between to see if ganache is smooth.
  • Let ganache cool to room temperature while you make the frosting.

To make the fudge buttercream frosting:

  • Place all ingredients in a food processor and pulse to incorporate. Process for a few seconds until smooth. If needed, scrape down any stray bits from the side of the bowl and pulse again for a few seconds.

To assemble the cake:

  • Place one cooled cake layer onto a plate or cake stand. Spread about 1 cup fudge buttercream frosting on top, and cover with about ½ cup of the ganache. Repeat with remaining cake layers and filling. (Filling amounts are for a 4-layer cake. If you are doing only 2 or 3 layers, you can be more generous with the frosting and ganache.)
  • Cover entire cake with remaining fudge frosting. Top with remaining ganache, letting it drip down the sides as desired. Chill in fridge for at least 1 hour to firm up. Let cool to room temperature 30 minutes before serving.

Notes

NOTES

  • Coffee helps enhance the chocolate flavor of the cake. The cake will not have a coffee taste. You can brew coffee for this recipe, or combine 1¼ cup hot water with 2 teaspoons instant espresso.
  • I used Hershey’s Special Dark cocoa for this cake.
  • Which size cake pan and how many you choose to use is up to you and the look you want. 8-inch pans will yield a taller, narrower cake than 9-inch pans. Do not fill cake pans more than 2/3 full or they may overflow in the oven.
  • Bake time will vary based on pan size and how much batter is in the pan. Time listed in this recipe is for cakes baked in 2 8×3-inch pans. Cakes baked in 9-inch pans or more than 2 8-inch pans will bake faster. Start checking at 20 minutes. When they appear dry on top, open the oven and gently press with your finger. Cakes are done when they feel firm but bounce back, and a toothpick inserted comes out with moist crumbs.
Calories: 887kcal, Carbohydrates: 116g, Protein: 10g, Fat: 48g, Saturated Fat: 30g, Polyunsaturated Fat: 2g, Monounsaturated Fat: 12g, Trans Fat: 1g, Cholesterol: 134mg, Sodium: 477mg, Potassium: 437mg, Fiber: 6g, Sugar: 84g, Vitamin A: 1150IU, Vitamin C: 0.4mg, Calcium: 128mg, Iron: 5mg
Cuisine: American
Course: Dessert
Author: Annalise
Have you tried this recipe?I’d love to hear about it! Leave a rating and review below, or take a photo and tag it on Instagram @completelydelicious with #completelydelicious.