Fudgy Chocolate Ganache Cake
This cake is exactly what you want when a chocolate craving hits. It’s a dense, fudgy single layer with a glossy dark chocolate ganache that sets into a thin, shiny shell.
The batter comes together in one bowl and bakes into a rich, tender crumb that stays moist for days. It’s the kind of cake that looks fancy but asks for very little effort.
What Makes This Ganache Cake So Good
The cake itself gets its deep chocolate taste from a mix of cocoa powder and melted dark chocolate. Buttermilk keeps the crumb tender and a little tangy, so it never feels heavy.
The ganache is just two ingredients: heavy cream and finely chopped dark chocolate. It pours on smoothly, sets to a mirror finish, and cracks beautifully when you slice. I love that it tastes even better the next day, making it ideal for baking ahead.
Ingredients
- 1 cup (240 ml) buttermilk, at room temperature: full-fat gives the best crumb; if you only have milk, stir in a tablespoon of lemon juice and let it sit 10 minutes
- 1/2 cup (120 ml) vegetable oil: keeps the cake moist for days
- 2 large eggs, at room temperature
- 1 teaspoon vanilla extract
- 1 1/2 cups (300 g) granulated sugar
- 1 1/2 cups (190 g) all-purpose flour
- 3/4 cup (65 g) unsweetened cocoa powder: Dutch-processed tastes smoother and less sharp
- 1 1/2 teaspoons baking powder
- 1/2 teaspoon baking soda
- 1/2 teaspoon fine sea salt
- 4 ounces (115 g) dark chocolate (60–70% cacao), melted and slightly cooled
- 8 ounces (225 g) dark chocolate (60–70% cacao), finely chopped
- 1 cup (240 ml) heavy cream
- Flaky sea salt, for garnish (optional)
Variations and Substitutions
- Swap the buttermilk: use whole milk soured with 1 tablespoon vinegar or lemon juice, let it stand 5 minutes
- Gluten-free: replace the flour with a 1-to-1 gluten-free blend that has xanthan gum
- Sweeter ganache: use semi-sweet chocolate instead of dark, and keep the cream amount the same
- Dairy-free: use a neutral oil, dairy-free yogurt thinned with a little water to mimic buttermilk, and vegan cream for the ganache (coconut cream works)
- Add espresso: stir 1 teaspoon instant espresso powder into the wet ingredients to deepen the chocolate flavor without adding coffee taste
For a flourless version, try my Intense Flourless Chocolate Torte.
How To Make Fudgy Chocolate Ganache Cake
Step 1: Mix the Batter
Preheat your oven to 350°F (175°C) and grease a 9-inch round cake pan, lining the bottom with parchment if you like. In a large bowl, whisk together 1 cup buttermilk, 1/2 cup oil, 2 eggs, 1 teaspoon vanilla, and 1 1/2 cups sugar until the mixture looks smooth and the sugar starts to dissolve, about 1 minute.
Sift in 1 1/2 cups flour, 3/4 cup cocoa, 1 1/2 teaspoons baking powder, 1/2 teaspoon baking soda, and 1/2 teaspoon salt. Fold gently with a spatula just until you see only a few streaks of flour left. Stir in the 4 ounces of melted dark chocolate, mixing until the batter is uniform and glossy. Stop as soon as no dry pockets remain; overworking it will make the cake tough.
Step 2: Bake the Cake
Pour the batter into the prepared pan and smooth the top. Bake on the middle rack for 32 to 35 minutes, until a toothpick inserted in the center comes out with a few moist crumbs attached, not raw batter. The top should spring back lightly when pressed.
Let the cake cool in the pan for 10 minutes, then turn it out onto a wire rack. Leave it until completely cool, at least 1 hour. A warm cake will melt the ganache, so take your time here.
Step 3: Heat and Stir the Ganache
Put 8 ounces of finely chopped dark chocolate in a heatproof bowl. In a small saucepan, heat 1 cup heavy cream over medium heat just until tiny bubbles form around the edges. Do not let it boil. Pour the hot cream over the chocolate and let it sit untouched for 2 minutes.
Gently whisk from the center outward until the ganache is smooth and glossy. If it feels thin, let it cool at room temperature, stirring now and then, for 10 to 15 minutes. You want it thick enough to coat the back of a spoon but still pourable.
Step 4: Glaze and Slice
Set the cooled cake on a wire rack over a baking sheet to catch drips. Slowly pour the ganache over the center, letting it flow over the sides. Use an offset spatula to guide it if a spot is bare, but the ganache should coat the cake in an even layer on its own. Let the ganache set for 30 minutes at room temperature, or 15 minutes in the fridge, until it loses its stickiness and firms up.
Scatter a pinch of flaky sea salt over the top just before serving, if you like. Slice with a hot knife (run it under hot water and wipe dry) for clean pieces. The cake keeps beautifully, getting even fudgier overnight.
A Few Notes for the Best Ganache Cake
- Bring eggs and buttermilk to room temperature so the batter emulsifies smoothly; cold ingredients can make the cake a little dense.
- Chop the chocolate for the ganache very fine. Large pieces won’t melt evenly and can leave lumps.
- If your ganache looks grainy or split, whisk in a tablespoon of warm milk or cream a little at a time until it smooths out.
- This cake is excellent the next day. Bake the cake a day ahead, wrap it well, and glaze it when you’re ready to serve.
Bake times depend on your pan:
| Pan Type | Size | Bake Time (mins) |
|---|---|---|
| Round cake pan | 9 inches | 32–35 |
| Round cake pan | 8 inches | 35–38 |
| Loaf pan | 9×5 inches | 40–45 |
Keeping Leftover Cake Fresh
Store the glazed cake covered at cool room temperature for up to 2 days, or refrigerated for up to 5 days. Let it come back to room temperature before serving for the best texture. To freeze, slice and wrap individual pieces in plastic and foil; they’ll keep for up to 3 months. Thaw at room temperature.
What to Serve with Fudgy Ganache Cake
Vanilla ice cream is the classic partner, the cold creaminess melts into the rich ganache. Fresh raspberries or strawberries cut through the intensity with their bright acidity. A dollop of lightly sweetened whipped cream adds a soft, airy contrast to the dense cake.
Frequently Asked Questions
Can I use milk chocolate for the ganache?
Yes, but the ganache will be sweeter and softer. Use 8 ounces of good milk chocolate and reduce the cream to 3/4 cup (180 ml) so it sets properly.
Why did my ganache turn out grainy?
The chocolate likely got too hot, or you stirred too hard while it cooled. Heat the cream until just steaming, not boiling, and stir the ganache gently. You can often fix a split batch by whisking in a little warm milk.
Can I make this cake gluten-free?
Sure. Replace the all-purpose flour with a 1-to-1 gluten-free blend that contains xanthan gum. The crumb will be slightly more tender but still fudgy.
How far ahead can I make the whole cake?
Bake the cake itself up to a day ahead and keep it wrapped at room temperature, or freeze it for up to a month. Glaze the day you plan to serve. Once glazed, it’s good at room temperature for 2 days or in the fridge for 5.
Fudgy Chocolate Ganache Cake Recipe
Ingredients
Method
- Preheat oven to 350°F (175°C). Grease a 9-inch round cake pan and line with parchment. Whisk buttermilk, oil, eggs, vanilla, and sugar until smooth.
- Sift in flour, cocoa, baking powder, baking soda, and salt. Fold until just combined, then stir in melted chocolate. Pour into pan.
- Bake 32 to 35 minutes until a toothpick comes out with moist crumbs. Cool in pan 10 minutes, then turn onto a rack to cool completely.
- Place chopped chocolate in a bowl. Heat cream until just steaming, pour over chocolate, and let sit 2 minutes. Whisk until smooth; cool until thickened but pourable.
- Pour ganache over the cooled cake, letting it drip down the sides. Let set at room temperature 30 minutes. Garnish with flaky salt and slice with a hot knife.
