Moist Double Chocolate Banana Cake with Rich Frosting Layers

This double chocolate banana layer cake is the ultimate treat when I want something indulgent, moist, and full of bold flavor. It combines the richness of cocoa with the natural sweetness of ripe bananas, layered with a luscious chocolate frosting that makes every bite feel like a celebration.

Why You’ll Love This Recipe

I love how this cake brings together the deep flavor of chocolate and the subtle sweetness of banana into a perfectly moist crumb. It’s a fantastic way to use overripe bananas, and the two layers make it feel extra special—perfect for birthdays, gatherings, or when I’m just craving something chocolatey and comforting. The best part? The banana keeps it soft for days, so I can enjoy it longer.

Ingredients

(Here’s a tip: Check out the full list of ingredients and measurements in the recipe card below.)

• All-purpose flour

• Unsweetened cocoa powder

• Baking powder

• Baking soda

• Salt

• Ripe bananas, mashed

• Granulated sugar

• Brown sugar

• Eggs

• Vegetable oil or melted butter

• Vanilla extract

• Buttermilk or milk + vinegar

• Semi-sweet chocolate chips (optional, for extra richness)

For the Chocolate Frosting:

• Unsalted butter, softened

• Powdered sugar

• Unsweetened cocoa powder

• Heavy cream or milk

• Vanilla extract

• Pinch of salt

Directions

1. I preheat the oven to 350°F (175°C) and grease two 8-inch round cake pans. I also line the bottoms with parchment paper for easy release.

2. In a bowl, I whisk together the flour, cocoa powder, baking soda, baking powder, and salt.

3. In a separate large bowl, I mash the bananas and mix in the sugars, eggs, oil, and vanilla.

4. I add the dry ingredients to the wet ingredients, alternating with buttermilk, and stir until just combined. If I’m using chocolate chips, I fold them in at the end.

5. I divide the batter evenly between the pans and bake for 30–35 minutes, or until a toothpick inserted comes out clean.

6. After cooling the cakes completely, I make the frosting by beating together butter, cocoa powder, powdered sugar, vanilla, and cream until smooth and fluffy.

7. I layer the cakes with frosting between and over the top, smoothing it with a spatula or keeping it rustic for a homemade look.

Servings and timing

This recipe serves 10–12 slices, depending on how generous I am. Prep takes around 20 minutes, baking about 30–35 minutes, and cooling/frosting adds another 30 minutes. Altogether, I usually have this finished in about 1.5 hours.

Variations

Sometimes I add a layer of peanut butter between the cakes or swirl it into the frosting for a twist. I’ve also made this as cupcakes, baking them for 18–22 minutes. If I’m out of buttermilk, I use milk mixed with a teaspoon of vinegar or lemon juice and let it sit for 5 minutes.

storage/reheating

I store the cake covered at room temperature for up to 2 days, or in the fridge for up to 5 days. To serve, I let refrigerated slices sit at room temperature for 15–20 minutes to soften. It also freezes beautifully—both frosted or unfrosted layers wrapped tightly in plastic and foil for up to 2 months.

FAQs

Can I use frozen bananas?

Yes, I’ve used thawed frozen bananas many times. I just make sure to drain any excess liquid before mixing them in.

Can I make this cake in one pan?

If I use a deep 9-inch pan, I can bake it as one layer and slice it in half later. I just increase the baking time and check doneness with a toothpick.

Is the cake very sweet?

It’s nicely balanced. The cocoa and banana mellow out the sweetness, especially if I use dark chocolate chips or a bittersweet frosting.

Can I make the frosting ahead of time?

Yes, I often make the frosting a day in advance and store it in the fridge. Before using, I let it soften and re-whip it for a fluffy texture.

What if I don’t have buttermilk?

I mix regular milk with 1 tablespoon of vinegar or lemon juice and let it sit for 5 minutes—it works as a perfect substitute.

Conclusion

This double chocolate banana cake is one of those desserts that feels both decadent and down-to-earth. It’s moist, chocolatey, and full of banana flavor, with layers of rich frosting that make it perfect for any celebration—or just because. When I want something sweet, soft, and absolutely satisfying, this cake never lets me down.