With an intense banana and a rich peanut butter flavor, this Sourdough Discard Banana Snack Cake will be your new favorite way to use up overripe bananas and excess discard.
I absolutely love banana bread, but when I accumulate too many overripe bananas, I love making this peanut butter banana snack cake! It's lighter and airier than a normal banana bread with a rich flavor thanks to the addition of sourdough discard and peanut butter.
What you need
- All-purpose flour - the low protein content of all-purpose imparts a soft, tender texture to this cake
- Baking soda - the main leavening agent, makes the cake rise and helps with browning
- Kosher salt - intensifies the flavors of the rest of the ingredients
- Peanut butter - adds a rich flavor to the cake
- Unsalted butter - adds richness and softness
- Granulated sugar - adds sweetness, structure and tenderizes the crumb
- Sourdough discard - adds a tangy flavor and added moisture which makes this cake taste fresher for longer
- Whole milk - loosens up the batter and adds moisture
- Eggs - adds richness and structure
- Overripe bananas - overripe bananas are essential for great results, it adds sweetness and intense flavor
- Vanilla extract - adds a rich flavor and additional sweetness
- 70% chocolate (optional) - I love topping my snack cake with chocolate chunks but you can substitute with nuts or dried fruit
- Whisk together flour, baking soda and salt
- Cream peanut butter, butter and sugar using an electric mixer
- Add eggs in one at a time
- Stir in bananas, sourdough discard and vanilla into batter
- Fold flour mixture into batter a third at a time, alternating with milk to loosen up the batter
- Pour batter into prepared baking pan
- Sprinkle chopped chocolate over batter
- Bake cake at 350 F for 40 to 50 minutes
Sourdough Discard Banana Snack Cake
- 156 grams 1 ⅓ cup all-purpose flour
- 6 grams ½ teaspoon salt
- 3 grams ¼ teaspoon baking soda
- 56 grams 4 tablespoons unsalted butter, softened
- 75 g ⅓ cup peanut butter
- 250 g 1 ¼ cup granulated sugar
- 100 grams 2 large eggs
- 56 g ¼ cup sourdough discard
- 7 g 2 teaspoons vanilla or rum
- 28 grams 2 tablespoons milk
- 227 grams 3 whole overripe bananas, mashed
- 60 grams 2 oz chocolate chunks
- Preheat your oven to 350 F (176 C). Line an 8-inch square baking pan with parchment paper.
- Whisk together flour, salt and baking soda and set aside.
- Using a stand mixer or hand mixer, cream together the peanut butter, butter and sugar until the mixture appears light and fluffy. Add eggs one at a time until each is fully combined.
- Add bananas, sourdough discard and vanilla until well-incorporated.
- Fold in half of the flour mixture with a spatula until the flour is hydrated. Add milk and the remaining flour until fully incorporated but do not overmix or your cake may turn out rubbery.
- Pour batter into your prepared baking pan and bake cake for 40 to 50 minutes or until a toothpick inserted into the center comes out clean.