The afternoon I made this cake, the house was already busy before the oven ever warmed up. My granddaughter had dragged a chair across the kitchen floor so she could “help,” my husband was at the table reading the paper aloud in bits and pieces, and the radio hummed softly with an old tune I’d nearly forgotten.
A neighbor had stopped by earlier with a sack of bananas that were a day past pretty, and I hated the thought of them going to waste. As I mashed them, I remembered school potlucks from my teaching days, where sheet cakes disappeared faster than anything else on the table.
Those were the desserts people cut just a sliver of, then quietly came back for more. I wanted something playful but familiar, a dessert that felt like a celebration without being fussy. The idea of a banana split kept popping into my head, all those bright colors and happy toppings.
By the time the cake went into the oven, the kitchen felt lighter, almost festive. That’s usually a good sign that a recipe is heading in the right direction.
Short Description
This cheerful banana split sheet cake blends soft banana cake with creamy banana and strawberry buttercreams, finished with a glossy chocolate drizzle, sprinkles, and cherries for a nostalgic, crowd-pleasing dessert.
Key Ingredients
Banana Cake
- 4 egg whites, room temperature
- ¾ cup buttermilk
- ⅔ cup sour cream
- 1 tablespoon vanilla
- 1 teaspoon banana extract optional
- ⅓ cup vegetable oil
- 1 cup ripe mashed bananas about 2 bananas
- 1 box 15.25 oz white cake mix
Small Batch Banana Buttercream
- 2 sticks unsalted butter 1 cup
- 1 pinch salt
- 2 teaspoons vanilla
- ½ teaspoon banana extract
- ⅛ cup heavy cream
- 4 to 5 cups powdered sugar
- 1 drop yellow gel coloring
Small Batch Strawberry Buttercream
- 2 sticks unsalted butter 1 cup
- 1 pinch salt
- 2 teaspoons vanilla
- 1 teaspoon strawberry emulsion
- ½ cup freeze dried strawberry powder measured after processing
- ¼ cup heavy cream
- 4 to 5 cups powdered sugar
Ganache Drizzle
- 1 cup chocolate candy melts
- ½ cup heavy cream
Extras
- 1 cup rainbow sprinkles
- 1 cup stem-on maraschino cherries
Tools Needed
- 9×13 inch baking pan
- Large mixing bowl
- Whisk
- Stand mixer with paddle attachment
- Offset icing spatula
- Scalloped cake scraper
- Piping bag with 1M piping tip
- Microwave-safe bowl
- Squeeze bottle
- Cooling rack
Cooking Instructions
Step 1: Prepare the Pan and Oven
Preheat the oven to 325°F using convection bake. Lightly coat a 9×13 pan with shortening, then dust with flour, tapping out the excess. Set aside.
Step 2: Mix the Banana Cake Batter
In a large bowl, hand-whisk the egg whites, buttermilk, sour cream, vanilla, banana extract if using, vegetable oil, and mashed bananas until smooth. Sift in the white cake mix and gently stir just until combined. Avoid overmixing, as this keeps the cake tender.
Step 3: Bake the Cake
Pour the batter evenly into the prepared pan. Bake for 25 to 27 minutes. The cake is done when the center springs back lightly and a toothpick comes out clean. Cool on a rack in the pan, or turn out if you plan to frost the sides.
Step 4: Make the Banana Buttercream
Using a stand mixer with the paddle, whip the butter on medium speed until light and fluffy. Add salt, vanilla, banana extract, and heavy cream, then mix again.
Gradually add powdered sugar and whip on high speed for 2 minutes. If the frosting feels stiff, add heavy cream 1 tablespoon at a time. Tint with yellow gel coloring. Hand-beat with a wooden spoon to remove air bubbles.
Step 5: Make the Strawberry Buttercream
Whip the butter until fluffy. Add salt, vanilla, strawberry emulsion, strawberry powder, and heavy cream.
Mix well, then add powdered sugar and whip on high speed for 2 minutes. Adjust with extra cream if needed. Hand-beat to smooth, then transfer to a piping bag fitted with a 1M tip.
Step 6: Prepare the Ganache
Place chocolate candy melts and heavy cream in a microwave-safe bowl. Heat for 30 seconds and stir. Continue heating in 10 second intervals, stirring each time, until smooth. Transfer to a squeeze bottle.
Step 7: Assemble the Cake
Spread the banana buttercream evenly over the cooled cake using an offset spatula. Use a scalloped cake scraper to create a patterned surface.
Drizzle chocolate ganache across the top, then sprinkle rainbow sprinkles around the outer edge. Pipe strawberry buttercream swirls along the border and top each swirl with a maraschino cherry.
Why You’ll Love This Recipe
Classic Comfort: Familiar banana split flavors in an easy, sliceable cake.
Simple and Approachable: Uses a cake mix with homemade touches for dependable results.
Crowd Friendly: Perfect for gatherings, birthdays, or potlucks.
Balanced Sweetness: Fruit-forward buttercreams keep it from feeling overly rich.
Mistakes to Avoid & Solutions
Overmixing the Batter
This can make the cake dense. Stir only until the mix is incorporated.
Frosting a Warm Cake
Warm cake melts buttercream. Allow the cake to cool completely before frosting.
Runny Buttercream
Add powdered sugar gradually and chill briefly if needed to firm it up.
Thick Ganache
Stir in 1 tablespoon warm cream to loosen the texture.
Serving and Pairing Suggestions
Serve chilled or at room temperature, cut into generous squares.
Pair with fresh strawberries or sliced bananas on the side.
A cup of coffee or a tall glass of cold milk balances the sweetness.
Ideal for buffet tables or family-style dessert spreads.
Storage and Reheating Tips
Store covered in the refrigerator for up to 4 days.
Bring slices to room temperature before serving for best texture.
Freeze unfrosted cake tightly wrapped for up to 2 months.
FAQs
1. Can I make this cake ahead of time?
Yes, bake the cake a day ahead and frost the next day for freshest results.
2. Can I skip the banana extract?
Absolutely. The mashed bananas provide plenty of flavor.
3. What if I don’t have freeze dried strawberries?
You can substitute strawberry jam, though the frosting will be softer.
4. Can this be made gluten free?
Use a gluten-free white cake mix and follow the same steps.
5. How do I keep the frosting smooth?
Hand-beating with a wooden spoon helps remove air bubbles.
Tips & Tricks
Mash bananas until smooth for even texture.
Chill buttercream briefly if piping details soften.
Use a warm spatula for cleaner frosting edges.
Recipe Variations
Chocolate Banana Split Cake
Replace white cake mix with chocolate cake mix. Keep the rest of the recipe the same.
Pineapple Twist
Add ½ cup finely crushed, well-drained pineapple to the batter for a tropical note.
Lighter Frosting
Swap half the butter in each frosting with cream cheese for a tangy balance.
Final Thoughts
When I finally set this cake on the table, the room went quiet in that good way that means people are focused. My granddaughter studied the cherries like little treasures, carefully choosing which slice she wanted. Watching everyone enjoy it reminded me why I keep baking, even on busy days.
This cake carries a bit of fun, a bit of nostalgia, and plenty of comfort. It doesn’t ask for perfection, just a willingness to share. That’s the kind of recipe I trust and return to. If you make it, I hope it brings the same warmth to your table. Desserts like this have a way of staying in the memory long after the plates are cleared.
Banana Split Sheet Cake
Ingredients
Banana Cake
- 4 egg whites room temperature
- ¾ cup buttermilk
- ⅔ cup sour cream
- 1 tablespoon vanilla
- 1 teaspoon banana extract optional
- ⅓ cup vegetable oil
- 1 cup ripe mashed bananas about 2 bananas
- 1 box 15.25 oz white cake mix
Small Batch Banana Buttercream
- 2 sticks unsalted butter 1 cup
- 1 pinch salt
- 2 teaspoons vanilla
- ½ teaspoon banana extract
- ⅛ cup heavy cream
- 4 to 5 cups powdered sugar
- 1 drop yellow gel coloring
Small Batch Strawberry Buttercream
- 2 sticks unsalted butter 1 cup
- 1 pinch salt
- 2 teaspoons vanilla
- 1 teaspoon strawberry emulsion
- ½ cup freeze dried strawberry powder measured after processing
- ¼ cup heavy cream
- 4 to 5 cups powdered sugar
Ganache Drizzle
- 1 cup chocolate candy melts
- ½ cup heavy cream
Extras
- 1 cup rainbow sprinkles
- 1 cup stem-on maraschino cherries
Instructions
- Preheat the oven to 325°F on convection bake. Grease a 9×13 pan with shortening, dust lightly with flour, and set aside.
- In a large bowl, whisk the egg whites, buttermilk, sour cream, vanilla, banana extract if using, oil, and mashed bananas until smooth. Sift in the cake mix and gently stir just until combined.
- Pour the batter into the prepared pan and bake for 25 to 27 minutes, until the center springs back and a toothpick comes out clean. Cool in the pan on a rack or turn out if frosting the sides.
- Beat the butter on medium speed until light and fluffy. Add salt, vanilla, banana extract, and heavy cream. Gradually mix in powdered sugar and whip on high for 2 minutes. Add more cream if needed, tint yellow, then hand-beat to remove air bubbles.
- Beat the butter until fluffy. Add salt, vanilla, strawberry emulsion, strawberry powder, and heavy cream. Mix in powdered sugar and whip on high for 2 minutes. Adjust with cream if needed, hand-beat smooth, and transfer to a piping bag fitted with a 1M tip.
- Combine chocolate candy melts and heavy cream in a microwave-safe bowl. Heat for 30 seconds, stir, then continue heating in 10-second intervals until smooth. Transfer to a squeeze bottle.
- Spread the banana buttercream evenly over the cooled cake. Use a scalloped scraper to create texture, drizzle with ganache, add sprinkles around the edge, pipe strawberry buttercream swirls, and finish each with a maraschino cherry.
