Introduction
There’s something magical about the way bananas and chocolate come together—and when you layer them into a cake? Pure heaven. This Double Chocolate Banana Layer Cake is the kind of dessert that demands a second slice, not because it’s overly indulgent, but because it’s just that good. Moist banana-rich layers, studded with dark chocolate chunks and wrapped in velvety chocolate ganache, make each bite a blend of creamy, tender, and rich. The aroma alone—ripe bananas, melted cocoa, a whisper of vanilla—transforms your kitchen into something special. Whether you’re celebrating a birthday or just craving something sweet, this cake delivers. And I promise, you’ll want to read on to discover all the ways you can make it uniquely yours.
Why You’ll Love This Recipe
Ever baked a cake that turns out too dry or dense? I’ve been there. That’s why I crafted this Double Chocolate Banana Layer Cake to be nearly foolproof—ultra-moist from mashed ripe bananas, with deep chocolate flavor that comes from using both cocoa powder and melted chocolate. The result is a cake that’s indulgent but balanced, rich but not cloying.
I made this cake for my brother’s birthday last summer, and let me tell you—people went silent during the first bite. My grandmother, a die-hard classic banana bread lover, raised her eyebrows and said, “Well, this is different—but in a good way.” That’s when I knew it was a keeper.
The best part? You can switch it up—add nuts, swap the frosting, or even bake it as cupcakes. Keep reading for the full details—you’ll want to bookmark this one.
Ingredients
Dry Ingredients
- All-purpose flour (2 ¼ cups)
Forms the structure of the cake—sift it for the lightest texture. - Unsweetened cocoa powder (¾ cup)
Use Dutch-processed for a deep, mellow chocolate flavor. Natural cocoa works too for a bit more bitterness. - Baking powder (1 ½ tsp) and baking soda (1 tsp)
Leavening agents that keep the cake fluffy—don’t skip these! - Salt (½ tsp)
Enhances sweetness and balances flavors.
Wet Ingredients
- Ripe bananas (3 large, mashed)
The star ingredient. Overripe bananas with black spots are best—natural sweetness and moisture galore. - Granulated sugar (1 cup) & brown sugar (½ cup)
Brown sugar adds a hint of molasses, giving depth and chewiness. - Large eggs (2)
For binding and richness. - Vanilla extract (1 ½ tsp)
Brings out the banana and chocolate flavors beautifully. - Buttermilk (1 cup)
Makes the cake extra tender. Substitute with milk + 1 tbsp lemon juice if needed. - Vegetable oil (½ cup)
Creates a moist crumb that stays soft for days.
Chocolate
- Semi-sweet chocolate chunks (1 cup)
Melty pockets of chocolate throughout. Chips work, but chunks melt better. - Dark chocolate (4 oz, melted)
Boosts the chocolate flavor and gives a luxurious texture.
Ganache Frosting
- Heavy cream (1 cup)
The base of a glossy, rich ganache. - Dark chocolate (8 oz, chopped)
Choose a quality bar—this is what everyone will taste first. - Unsalted butter (2 tbsp)
Adds shine and smoothness.
How to Make Double Chocolate Banana Layer Cake
1. Prep Your Pans and Ingredients
Preheat your oven to 350°F (175°C). Grease and line two 9-inch round cake pans with parchment paper.
Mash your bananas well—they should be smooth with a few tiny chunks. Melt your dark chocolate and let it cool slightly.
2. Mix Dry Ingredients
In a large bowl, whisk together the flour, cocoa powder, baking powder, baking soda, and salt. This removes lumps and ensures even distribution.
3. Blend Wet Ingredients
In another bowl, beat together mashed bananas, both sugars, eggs, vanilla, buttermilk, and oil until combined. Stir in the cooled melted chocolate.
4. Combine and Add Chocolate Chunks
Slowly fold the dry mixture into the wet mixture. Mix until just combined—don’t overmix. Gently fold in the chocolate chunks.
5. Bake to Perfection
Divide the batter evenly between your prepared pans. Bake for 30–35 minutes, or until a toothpick inserted comes out with a few moist crumbs.
Let cakes cool in the pans for 10 minutes, then transfer to wire racks to cool completely.
6. Make the Ganache
Heat cream in a saucepan until it just begins to simmer. Pour over chopped chocolate and butter in a bowl. Let sit for 5 minutes, then whisk until glossy.
7. Assemble and Frost
Once cakes are cool, level the tops if needed. Spread a generous layer of ganache between them, then coat the entire cake. Chill for 30 minutes before serving for cleaner slices.
Variations
- Peanut Butter Swirl
Add ½ cup of peanut butter to the batter for a nutty twist. - Mocha Madness
Add 1 tsp of espresso powder to the dry ingredients to enhance the chocolate. - Tropical Touch
Fold in shredded coconut and chopped macadamia nuts for a beachy vibe. - Salted Caramel Drizzle
Drizzle homemade caramel over the ganache before serving. - Gluten-Free Option
Use a 1:1 gluten-free flour blend—just ensure it contains xanthan gum. - Holiday Spice Edition
Add 1 tsp cinnamon and ¼ tsp nutmeg for a cozy, festive version.
Double Chocolate Banana Layer Cake
Ingredients
Dry Ingredients
- 2 ¼ cups all-purpose flour sifted
- ¾ cup unsweetened cocoa powder Dutch-processed or natural
- 1 ½ tsp baking powder
- 1 tsp baking soda
- ½ tsp salt
Wet Ingredients
- 3 ripe bananas mashed
- 1 cup granulated sugar
- ½ cup brown sugar packed
- 2 large eggs
- 1 ½ tsp vanilla extract
- 1 cup buttermilk
- ½ cup vegetable oil
- 4 oz dark chocolate melted & cooled slightly
Add-ins
- 1 cup semi-sweet chocolate chunks
- Ganache Frosting
- 1 cup heavy cream
- 8 oz dark chocolate chopped
- 2 tbsp unsalted butter
Instructions
Prep the Cake Pans:
- Preheat oven to 350°F (175°C). Grease two 9-inch cake pans and line with parchment rounds.
Whisk Dry Ingredients:
- In a large bowl, whisk flour, cocoa powder, baking powder, baking soda, and salt. Set aside.
Mix Wet Ingredients:
- In another bowl, beat mashed bananas, sugars, eggs, vanilla, buttermilk, and oil until well combined. Stir in melted dark chocolate.
Combine Wet + Dry:
- Gradually add dry ingredients to wet mixture, folding gently. Do not overmix.
Add Chocolate Chunks:
- Fold in the chocolate chunks. Divide batter evenly between the pans.
Bake:
- Bake for 30–35 minutes, or until a toothpick comes out with a few moist crumbs. Cool in pans for 10 minutes, then transfer to wire racks to cool fully.
Make Ganache:
- Heat cream in a saucepan just until simmering. Pour over chopped chocolate and butter in a bowl. Let sit 5 minutes, then whisk until smooth and glossy. Cool until spreadable.
Assemble:
- Level cake layers if needed. Spread ganache between the layers, then cover the top and sides. Chill cake for 30 minutes before slicing.
Notes
- Peanut Butter Swirl: Add ½ cup peanut butter to the batter for a nutty depth.
- Mocha Twist: Mix in 1 tsp espresso powder to dry ingredients.
- Gluten-Free: Use a 1:1 GF baking blend (with xanthan gum).
- Cupcake Option: Bake in lined muffin tins for 18–20 minutes.
- Freeze Ahead: Wrap unfrosted cake layers and freeze up to 1 month.
- Decorating Tip: Top with banana chips, chopped nuts, or cocoa nibs for crunch.
Nutrition
FAQ
Can I make this cake ahead of time?
Yes! Bake the layers a day in advance, wrap tightly, and refrigerate. Assemble the day you serve.
How should I store leftovers?
Store in an airtight container at room temperature for 2 days or refrigerate for up to 5 days.
Can I freeze this cake?
Absolutely. Wrap individual slices in plastic wrap and foil, then freeze. Thaw overnight before enjoying.
What if I don’t have buttermilk?
Mix 1 cup milk with 1 tbsp lemon juice or vinegar. Let sit 5 minutes before using.
Is this recipe dairy-free?
Not as written, but you can use plant-based milk and coconut cream for the ganache.
My cake sank in the middle—what happened?
Overmixing or underbaking are common causes. Make sure your oven is fully preheated and avoid opening the door too early.
Closing Thoughts
There’s something truly special about sharing a homemade cake—especially one as rich and nostalgic as this Double Chocolate Banana Layer Cake. I first baked it on a rainy afternoon when the bananas on my counter begged for attention, and it’s since become a family favorite. It captures the warmth of tradition with a bold, chocolaty twist—just the kind of dessert that brings people together. Whether you follow the recipe to the letter or make it your own, I hope it becomes part of your celebration table too. Happy baking!