Easy Banana Snack Cake With Dark Chocolate Buttercream

Amy Manes
by Amy Manes
12 slices
45 min

This easy banana snack cake is all that you will need to satisfy your sweet tooth! If you’re a big fan of traditional banana bread, then you are going to love this cake inspired by a classic dessert! This banana cake is super moist and is topped with dark chocolate buttercream for extra yumminess! It really is the perfect afternoon treat or after school snack for your kiddos! I like that this banana snack cake can be made year-round. You are definitely going to want to keep this banana snack cake recipe on hand for any and all occasions! It’s a crowd pleaser for sure!

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If you’re the type that loves a good loaf of traditional banana bread, then you will go nuts over this moist and easy banana cake! My favorite part is the dark chocolate buttercream, of course!

This banana cake is so great because it makes just a small 9×9 inch cake. It’s the perfect size for snacking!

Read on for my tips on how to make the best banana snacking cake!

Tips for Banana Snack Cake

In order to make this cake super moist and fluffy, follow these tips below!

  • Use extra brown bananas – I know you probably have some in your kitchen right now! The browner the bananas are, the sweeter they are. This makes them perfect for banana cake! Here’s a good tip too: If I have a ton of brown bananas, I peel and cut them into 3 or 4 pieces and freeze them in a ziplock bag. Then when I’m in the mood for banana cake, banana muffins, or banana bread, I just pull them out of the freezer to thaw and then bake away!
  • Use brown sugar – Yes, just brown sugar! This makes the cake super dense and moist, which I think is the perfect consistency for this banana snack cake!
  • Use room temperature ingredients – I always say this in my recipes, but it’s worth repeating! Room temperature ingredients are easier to mix into your dry ingredients, and you have less of a chance of overmixing the batter. This will keep your cake fluffy and thick!
  • Use full-fat sour cream – Or full-fat Greek yogurt if you prefer! Make sure you aren’t using fat-free sour cream because the fats keep the cake moist and flavorful!

High Altitude Instructions for Cakes

For reference, I live at 5,800 feet. These adjustments would likely give you the result that you are looking for if you live within a few hundred feet of where I am at. But high altitude baking can be a lot of trial and error! This should give you a starting point to go off of to experiment with your own ingredients at whatever elevation you live at! I would also recommend checking out this guide here.

High Altitude Adjustments for Banana Snack Cake

  • Flour – increase by 2 tbsp. Additional flour helps to strengthen the structure of the baked good so that it will rise correctly.
  • Brown Sugar – decrease by 1/2 tbsp. This should hold true at most high elevations. Always decrease your sugars by 1 tbsp. per cup.
  • Baking Soda– decrease to 1/2 tsp. You can see this table on King Arthur’s website for how to adjust leavening agents for higher elevations (scroll down a ways to the “Leavening” section on their site). For my elevation, I typically cut all leavening agents in half. This allows for the right chemical reactions to happen between the other ingredients for the perfect rise. If there is too much leavening within the batter, not all of it gets used up (not all of it reacts with the other ingredients). You are then left over with a soapy bitter-tasting baked good due to the excess baking soda or baking powder in the batter.
  • Baking Powder- decrease to 1/4 tsp. Same reasoning as for other leavening agents.
  • Eggs – use 3 eggs instead of 2. This will keep the baked good from drying out at a higher baking temperature and evaporation rate. If I am baking a cake or cupcakes, I like to add one more egg to increase the liquids in the recipe. This should hold true at most higher elevations, but experiment with it, of course!
  • Increase oven temperature to 365° F. Since rising and evaporation proceed more quickly at higher elevations, you will want to use a higher baking temperature to set the structure of the baked goods so that they don’t sink in the middle and dry out on the edges. I recommend starting with increasing the baking temperature stated in the recipe by 10° F – 15° F and going up from there in small increments (all the way up to 25° F increase if needed).
  • Decrease baking time by 5 or more minutes. This is because you will be baking at a higher temperature. You don’t want your dessert to burn! I usually decrease by 5-8 minutes per 30 minutes of baking time and adjust from there. Keep a close eye on your dessert in the oven while you are experimenting with time and baking temps.

Easy Banana Snack Cake With Dark Chocolate Buttercream
Recipe details
  • 12  slices
  • Prep time: 20 Minutes Cook time: 25 Minutes Total time: 45 min
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For the Banana Snack Cake
  • 1 1/2 cups all-purpose flour
  • 1 tsp baking soda
  • 1/2 tsp baking powder
  • 3/4 tsp salt
  • 1/2 tsp cinnamon
  • 1/2 cup light brown sugar (packed)
  • 3 medium, very ripe bananas (mashed)
  • 1/2 cup vegetable or canola oil
  • 1/2 cup full-fat sour cream (room temperature)
  • 2 tsp vanilla extract
  • 2 large eggs (room temperature)
For the Dark Chocolate Buttercream
  • 1/2 cup roughly chopped dark chocolate
  • 3/4 cup unsalted butter (room temperature)
  • 1/2 tsp vanilla extract
  • 1 cup + 2 tbsp powdered sugar
  • pinch of salt
For the Banana Snack Cake
Preheat oven to 350°F. Line a 9×9 inch square baking pan with parchment paper, leaving the edges hanging off of the side (to lift the cake out when it is done).
In a medium bowl, whisk together the flour, baking soda, baking powder, salt, cinnamon, and brown sugar. Set aside.
In a separate bowl, combine bananas, oil, sour cream, and vanilla. Stir in the eggs until everything is well combined.
Add the flour mixture to the banana mixture and stir until just barely combined (do not overmix). Pour the batter into the prepared baking pan and bake for 25-30 minutes, or until a toothpick inserted in the center comes out with a few moist crumbs.
Cool on a wire rack completely before frosting.
For the Dark Chocolate Buttercream
In a medium saucepan over low heat, melt the chopped chocolate until smooth. Once melted, remove from the heat to cool slightly.
In the bowl of a stand mixer fitted with the paddle attachment, or in a large bowl with a hand mixer, beat the butter on high speed until light and fluffy (about 3 minutes).
Add the vanilla extract and salt and beat on medium speed until incorporated.
Reduce the mixer to low speed and slowly add in the powdered sugar. Beat on low for 30 seconds and then increase the speed to medium-high and beat until smooth (about 3 minutes).
Stop the mixer and add the melted chocolate to the bowl. Mix on low speed until combined. Frost cooled cake with buttercream.
  • Cake can be stored in an airtight container for up to 3 days at room temperature.
  • Cake can be frozen and frosted later. Simply wrap in plastic wrap and foil and freeze for up to 1 month. Set cake out at room temperature before frosting.
  • High Altitude Directions:
  • -Flour – increase by 2 tbsp.
  • -Brown Sugar – decrease by 1/2 tbsp.
  • -Baking Soda – decrease to 1/2 tsp.
  • -Baking Powder – decrease to 1/4 tsp.
  • -Eggs – use 3 eggs instead of 2.
  • -Increase oven temperature to 365° F.
  • -Decrease baking time by 5 or more minutes
Amy Manes
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