Chocolate Banana Swirl Cake is a tender and indulgent dessert that marries the natural sweetness of ripe bananas with the richness of cocoa. Each slice reveals a beautiful marbled pattern, created by swirling banana and chocolate batters together. Finished with a light dusting of powdered sugar and a drizzle of chocolate syrup, this cake is as eye-catching as it is satisfying.

Why You’ll Love This Recipe

This cake offers the perfect balance of fruity and chocolaty flavors in every bite. It’s simple to prepare, makes use of overripe bananas, and results in a soft, moist crumb that stays fresh for days. Whether enjoyed with coffee, served as an after-dinner dessert, or packed in a lunchbox, Chocolate Banana Swirl Cake delivers comfort and decadence in equal measure.

ingredients

(Tip: You can find the complete list of ingredients and their measurements in the recipe card below.)

ripe bananas, mashed
granulated sugar
brown sugar
unsalted butter, softened
large eggs
sour cream
vanilla extract
all-purpose flour
baking soda
salt
unsweetened cocoa powder
milk
powdered sugar (for dusting)
chocolate syrup (for drizzling)

directions

Preheat the oven to 350°F (175°C). Grease and flour a loaf or cake pan.
In a large bowl, cream the butter with granulated sugar and brown sugar until light and fluffy.
Beat in the eggs one at a time. Stir in the mashed bananas, sour cream, and vanilla extract until smooth.
In a separate bowl, whisk together the flour, baking soda, and salt. Gradually fold the dry ingredients into the banana mixture until just combined.
Divide the batter evenly into two bowls. To one half, add the cocoa powder and milk, stirring until smooth.
Spoon alternating dollops of plain banana batter and chocolate batter into the prepared pan.
Use a knife or skewer to gently swirl the batters together, creating a marbled effect.
Bake for 50–60 minutes, or until a toothpick inserted in the center comes out clean.
Let the cake cool completely in the pan before transferring to a serving plate.
Dust with powdered sugar and drizzle with chocolate syrup just before serving.

Servings and timing

Servings: 8 slices
Prep Time: 15 minutes
Baking Time: 55 minutes
Total Time: 1 hour 10 minutes
Calories per serving: 320 kcal

Variations

Nutty Addition: Add chopped walnuts or pecans to the batter for added crunch.
Espresso Kick: Stir a teaspoon of instant espresso powder into the chocolate batter to deepen the flavor.
Mini Loaves: Divide the batter into smaller pans for individual portions.
Cinnamon Spice: Add a pinch of cinnamon or nutmeg to the banana batter for a warming touch.
Frosted Finish: Top with a chocolate or cream cheese glaze instead of powdered sugar for a richer presentation.

storage/reheating

Store the cake in an airtight container at room temperature for up to 3 days, or refrigerate for up to 5 days. To enjoy warm, microwave individual slices for 10–15 seconds. The cake also freezes well — wrap tightly in plastic wrap and store in a freezer-safe container for up to 1 month. Thaw overnight in the refrigerator before serving.

FAQs

Can I use Greek yogurt instead of sour cream?

Yes, plain full-fat Greek yogurt is a suitable substitute and will maintain the cake’s moisture.

What kind of cocoa powder should I use?

Unsweetened natural cocoa powder is best for this recipe. Dutch-processed can be used but will slightly alter the flavor.

Can I bake this in a bundt pan?

Yes, but adjust the baking time as needed and ensure the pan is well-greased to prevent sticking.

How do I get a good swirl effect?

Use a skewer or butter knife and make gentle figure-eight motions through the batter without overmixing.

Can I make this cake gluten-free?

Yes, substitute the flour with a 1:1 gluten-free baking blend. Be sure it contains xanthan gum for structure.

Why is my cake too dense?

Overmixing or using under-ripe bananas can lead to a dense texture. Mix just until combined and use very ripe bananas.

Can I reduce the sugar?

Yes, reduce each sugar by 1–2 tablespoons, though this may slightly affect the texture and sweetness.

Do I need to sift the cocoa powder?

It’s not required, but sifting can help avoid lumps in the chocolate batter.

Is it okay to use frozen bananas?

Yes, thaw and drain any excess liquid before mashing and using in the batter.

What can I serve this cake with?

It pairs beautifully with whipped cream, a scoop of vanilla ice cream, or a hot cup of coffee.

Conclusion

Chocolate Banana Swirl Cake is a delightful way to elevate traditional banana bread into something a little more indulgent. With rich chocolate ribbons woven through moist banana cake and a touch of sweetness on top, it’s a simple yet elegant bake that satisfies both fruit and chocolate lovers alike.