Looking for a delicious way to use up ripe bananas and sourdough starter? This Sourdough Banana Snack Cake with Brown Butter Cream Cheese Frosting is the ultimate treat — moist, tender, and bursting with banana flavor, all topped with a rich, nutty frosting you’ll want to eat by the spoonful.

Whether you’re using sourdough discard or active starter, this recipe fits right into your routine and adds a little magic to your day. It’s simple to make, perfect for sharing, and guaranteed to impress. Once you try it, this cake will be your go-to banana dessert.

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This sourdough banana snack cake with brown butter cream cheese frosting is soft, sweet, and made with pantry ingredients. It’s an easy way to use up ripe bananas and sourdough starter for a treat that’s just the right amount of indulgent.

More Sourdough Discard Recipes You’ll Love

• Moist Sourdough Almond Banana Bread (with Sour Cream)
• Sourdough Discard Oatmeal Chocolate Chip Cookies
• Easy Same Day Sourdough Cinnamon Rolls (Discard)
• Sourdough Jam Sheet Cake (Active or Discard)

Tools needed:

• Mixing bowls (one large, one medium, one small)

• Whisk 

• Spatula

• Measuring cups and spoons

• 8×8-inch square baking pan

• Small saucepan (for browning butter)

• Hand mixer or stand mixer (for frosting — optional but helpful)

 Ingredients & What They Do

• Ripe bananas – Add natural sweetness, moisture, and banana flavor.

• Sourdough starter (discard or active) – Adds tang, depth, and a tender crumb.

• Unsalted butter – Provides rich flavor and moisture; also used for the browned frosting.

• Granulated sugar – Sweetens the cake and helps with texture.

• Eggs – Bind the batter and add structure and richness.

• Vanilla extract – Enhances overall flavor with a warm, sweet note.

• Sour cream or plain yogurt – Keeps the cake moist and tender.

• All-purpose flour – Gives structure to the cake without making it dense. You can also use bread flour. I always recommend King Arthur or Bob’s Red Mill Flours. 

• Baking soda & baking powder – Work together to create lift and lightness.

• Cinnamon (optional) – Adds a warm, cozy flavor that complements banana.

• Salt – Balances sweetness and enhances flavor in both the cake and frosting.

• Cream cheese – Creates a tangy, creamy base for the frosting.

• Powdered sugar – Sweetens and smooths out the frosting.

• In a small light-colored saucepan, melt 115 g unsalted butter over medium heat.

• Stir gently as it foams, bubbles, and begins to turn golden.

• When it smells nutty and you see brown bits on the bottom, remove it from the heat right away.

• Pour the browned butter into a bowl and let it cool completely (you can chill it in the fridge for faster cooling, but don’t let it fully harden).

Beat the Cream Cheese

• In a medium bowl, beat 225 g softened cream cheese until smooth and fluffy (use a hand mixer or stand mixer for best results).

  Add Powdered Sugar & Vanilla

  • Add 180–200 g powdered sugar a little at a time, beating after each addition.

  • Add 1 tsp (5 g) vanilla extract and a pinch of salt to balance the sweetness.

  Beat until smooth and fluffy. Taste and adjust sweetness if needed.

Add Brown Butter

• Once the browned butter has cooled to room temperature, beat it into the cream cheese until fully combined and creamy. 

• PRO TIP: Place the brown butter into the fridge for about 20 minutes, stirring it every 5-7 mins, until it turns white but still soft.

Chill (Optional)

• If the frosting is too soft to spread, place it in the fridge for 10–15 minutes to firm up slightly before using.

Let me know in the comments if you bake it—I’d love to hear how it turns out for you!

Tag me @shakanranch or leave a comment below!

Sourdough Banana Snack Cake with Brown Butter Cream Cheese Frosting

This sourdough banana snack cake is soft, flavorful, and topped with a rich, nutty brown butter cream cheese frosting. It’s a great way to use up sourdough discard and overripe bananas — perfect for afternoon tea, lunchboxes, or a cozy dessert. With banana slices on top and a tangy-sweet frosting, it’s as beautiful as it is delicious.

Print Recipe Pin Recipe

Prep Time 25 minutes mins

Cook Time 35 minutes mins

Cooling Time 1 hour hr

Total Time 2 hours hrs

Course Dessert

Cuisine American

Equipment

• Mixing bowls
• Hand mixer or stand mixer
• Rubber spatula
• 8×8-inch (20×20 cm) square baking pan
• Saucepan (light-colored, for browning butter)
• Sifter or fine mesh sieve
• Parchment paper (optional)
• Offset spatula or spoon (for frosting)

Ingredients

  

Banana Cake

• 240  g ripe bananas mashed (about 2 medium)
• 200  g granulated sugar
• 115  g unsalted butter melted
• 2 large eggs
• 60  g sour cream or plain yogurt
• 5  g vanilla extract 1 tsp
• 2  g ground cinnamon ½–1 tsp, to taste
• 2  g salt ¼ tsp
• 120  g sourdough starter active or discard
• 5  g baking soda 1 tsp
• 190  g all-purpose flour
• 3  g baking powder ¾ tsp
• 1 ripe banana for topping, sliced into rings – optional

Brown Butter Cream Cheese Frosting

• 115  g unsalted butter for browning
• 225  g cream cheese softened
• 180 –200 g powdered sugar
• 5  g vanilla extract 1 tsp
• Pinch of salt

Instructions

 

Brown the Butter (Start First)

• In a small light-colored saucepan, melt 115 g unsalted butter over medium heat.
  115  g unsalted butter
• Stir as it foams and bubbles. When it turns golden and smells nutty, remove from heat.
• Pour into a heatproof bowl and let it cool completely (you can chill briefly, but don’t let it harden).

Prepare the Cake Batter

• Preheat oven to 175°C (350°F). Grease or line an 8×8-inch baking pan with parchment paper.
• In a large bowl, mash 240 g bananas until smooth.
  240  g ripe bananas
• Add the following ingredients one at a time, mixing after each:
• 200 g sugar
  200  g granulated sugar
• 115 g melted butter
  115  g unsalted butter
• 2 eggs
  2 large eggs
• 60 g sour cream or yogurt, 5 g vanilla extract, 2 g cinnamon, and 2 g salt.
  60  g sour cream or plain yogurt, 5  g vanilla extract, 2  g ground cinnamon, 2  g salt
• In a small bowl, mix 120 g sourdough starter with 5 g baking soda. Let sit for 1–2 minutes until bubbly, then stir into the batter.
  120  g sourdough starter, 5  g baking soda
• Sift in 190 g flour and 3 g baking powder. Fold with a spatula just until no dry streaks remain.
  190  g all-purpose flour, 3  g baking powder
• Pour batter into prepared pan and smooth the top. Add banana slices on top, if using.
  1 ripe banana

Bake

• Bake for 35–40 minutes, or until a toothpick comes out clean and the top springs back lightly.
• Let cake cool completely before frosting.

Make the Frosting

• Beat 225 g cream cheese until smooth.
  225  g cream cheese
• Add powdered sugar gradually, followed by vanilla and salt.
  180 –200 g powdered sugar, 5  g vanilla extract, Pinch of salt
• Beat in the cooled brown butter until smooth and creamy. Chill 10–15 minutes if frosting is too soft.

Frost the Cake

• Once the cake is completely cool, spread the frosting evenly over the top.
• Slice and enjoy!

Notes

• Sourdough discard or active starter both work well.
• For added flavor and visual appeal, use banana slices on top before baking.
• Store frosted cake in an airtight container in the fridge for up to 5 days.
• This cake freezes well (without frosting) for up to 2 months.

Keyword brown butter frosting, snack cake, sourdough banana cake