Fudgy Brownie Stack Cake with Chocolate Ganache
This brownie stack cake layers three fudgy brownie rounds with a silky dark chocolate ganache. It looks like a special occasion dessert but comes together with one simple brownie batter baked in three tins.
Serve it at a birthday party or just because it’s Tuesday. Each forkful is dense, rich, and impossibly chocolatey.
What Makes This Brownie Cake So Good
The brownie layers are baked just until set, so they stay gooey in the middle. The ganache firms up between them, giving a contrast between soft cake and creamy filling.
I keep coming back to this one because it’s endlessly flexible. Swap the ganache for peanut butter frosting or a quick caramel drip, and it becomes a whole new dessert.
It’s also a great make-ahead. The brownies improve after a few hours, and you can assemble it the night before.
Ingredients
- 1 cup unsalted butter: melted and cooled slightly, use European-style for extra richness
- 2 cups granulated sugar: white sugar gives the edges a chewy snap
- 3 large eggs: at room temperature so they blend smoothly
- 2 teaspoons vanilla extract: pure extract makes a difference here
- ¾ cup unsweetened cocoa powder: sift it to remove any lumps
- 1 cup all-purpose flour: spoon and level, do not scoop
- ½ teaspoon fine sea salt: it wakes up the chocolate
- 1 cup semisweet chocolate chips: optional, for soft melty pockets
For the ganache:
- 8 oz bittersweet chocolate (60-70% cacao): finely chopped so it melts evenly
- 1 cup heavy cream: plus an extra splash if the ganache looks too thick
Variations and Substitutions
- Swap butter for coconut oil: This works well for a dairy-free brownie. Refined coconut oil keeps the flavor neutral.
- Add 1 teaspoon espresso powder: It will not make the cake taste like coffee, it just makes the chocolate taste deeper.
- Use a different frosting: A thick peanut butter buttercream or a marshmallow fluff filling each change the character completely.
If you love this, try my Flourless Chocolate Torte for a rich, flour-free option.
How to Make Brownie Stack Cake
Step 1: Bake the Brownie Layers
Preheat the oven to 350°F (180°C). Butter three 8-inch round cake pans and line the bottoms with parchment paper. In a large bowl, whisk the melted 1 cup butter with the 2 cups sugar until smooth. Beat in the 3 eggs one at a time, then stir in the 2 teaspoons vanilla. Sift in the ¾ cup cocoa powder, 1 cup flour, and ½ teaspoon salt. Fold gently until just combined, do not overmix. Divide the batter evenly among the three pans (a kitchen scale helps). If using, scatter the chocolate chips over the tops.
Bake for 18 to 20 minutes, until the tops look dry and the edges pull away slightly. The centers will still be soft. Let them cool in the pans for 10 minutes, then turn out onto a wire rack to cool completely. The layers sink in the middle as they cool, that is expected.
Step 2: Stir the Chocolate Ganache
Place the finely chopped bittersweet chocolate in a heatproof bowl. Heat the 1 cup heavy cream in a small saucepan over medium heat until just steaming, do not let it boil. Pour the hot cream over the chocolate and let it sit for 2 minutes. Then stir slowly from the center outward until the mixture becomes glossy and smooth.
If there are still small lumps of chocolate, warm the bowl briefly over a pan of barely simmering water and stir again. Transfer the ganache to the fridge and chill for at least 2 hours, until it is cool and thick enough to hold its shape but not rock hard. If it becomes too firm, let it sit at room temperature for 10 minutes before whipping.
Step 3: Whip the Ganache
Using an electric mixer or a sturdy whisk, whip the chilled ganache on medium speed for about 1 minute. It will lighten in color and turn fluffy and spreadable, like a chocolate mousse. Stop as soon as soft peaks form. Overwhipping can make it grainy, so keep an eye on it.
If the ganache looks separated or grainy, you can rescue it by gently reheating it over a double boiler until smooth, then chilling and whipping again. Set aside about ½ cup for decorating if you like.
Step 4: Layer and Frost the Cake
Place one cooled brownie layer on a serving plate. Spread a generous scoop of the whipped ganache over it, right to the edges. Stack the second brownie on top and repeat. Top with the third brownie and spread the remaining ganache over the top and sides of the whole cake. Use an offset spatula to smooth it out, or leave swirls for a rustic look.
If you have reserved ganache, pipe a few rosettes on top. Scatter with chocolate curls, a dusting of cocoa powder, or a sprinkle of flaky sea salt to finish. Slice and serve right away, or chill for 30 minutes for cleaner cuts.
Tips for a Showstopping Stack
- Trim the brownies’ domed tops: Use a long serrated knife to level them. Crumble the trimmings and sprinkle them over the finished cake for decoration.
- Chill the assembled cake: After frosting, refrigerate for at least 30 minutes before slicing. This sets the ganache and keeps the layers from sliding.
- If the ganache splits while whipping: Gently reheat it over a double boiler, whisk until smooth, then chill and whip again.
- Make a crumb coat: Spread a thin layer of ganache over the entire cake, chill 15 minutes, then apply the final layer for a completely clean finish.
Bake time depends on your pan size:
| Pan Size | Bake Time (approx.) | Look For |
|---|---|---|
| 8-inch round | 18–20 mins | Dry top, edges pulling away, soft center |
| 9-inch round | 15–17 mins | Firm edges, center just set |
Storing Leftover Cake
Store the cake in the refrigerator, covered, for up to 4 days. Let slices come to room temperature before eating, the brownie layers will soften and the ganache becomes creamy again. Freezing: wrap the whole cake or individual slices tightly in plastic wrap and foil, then freeze for up to 1 month. Thaw overnight in the fridge.
What to Serve With This Brownie Stack Cake
A scoop of vanilla ice cream is a classic pairing, the cold creaminess cuts through the dense, fudgy brownie. For an afternoon slice, a strong espresso or black coffee balances the sweetness without competing. Fresh raspberries also work, their tartness brightens each bite.
Frequently Asked Questions
Can I make the brownie layers in advance and freeze them?
Yes. Wrap each cooled layer individually in plastic wrap and freeze for up to 1 month. Thaw them on the counter still wrapped, then assemble the cake.
My ganache is too runny to whip. What should I do?
It needs more chilling time. Put it back in the fridge for 30 minutes to 1 hour, checking until it feels thick and scoopable. If you are in a hurry, set the bowl over an ice bath to speed things up.
Can I use a 9×13-inch pan instead of rounds?
You can, but then it becomes a single layer sheet. Bake for about 22 to 25 minutes, cool, then cut into squares and stack with ganache as mini stacks. The texture will be the same.
Is it okay to skip the ganache and use a jar of frosting?
Absolutely. A good quality chocolate fudge frosting works if you are short on time. Warm it slightly so it spreads easily, and the assembled cake will still taste great.
Can I use gluten-free flour?
Yes, use a 1-for-1 gluten-free flour blend that contains xanthan gum. The batter will be slightly more delicate, so handle the baked layers with care.
Brownie Stack Cake Recipe
Ingredients
Method
- Preheat oven to 350°F (180°C). Butter three 8-inch round cake pans and line with parchment. Whisk melted butter and sugar until smooth. Beat in eggs one at a time, then vanilla. Sift in cocoa, flour, and salt; fold gently just until combined. Divide batter among pans, top with chocolate chips if using, and bake 18–20 minutes until just set. Cool in pans 10 minutes, then turn out to cool completely.
- Place chopped chocolate in a heatproof bowl. Heat cream until steaming, pour over chocolate, let sit 2 minutes, then stir until smooth. Chill at least 2 hours until thick but spreadable.
- Whip chilled ganache with an electric mixer on medium speed until fluffy and light, about 1 minute. Do not overwhip.
- Place one brownie layer on a plate, spread with a third of whipped ganache. Repeat with remaining layers. Frost top and sides with remaining ganache. Decorate if desired, then chill 30 minutes before slicing.
