Sourdough Banana Nut Bread (Printable)

Moist banana loaf with sourdough, toasted walnuts, and a crisp brown sugar topping.

# What you'll need:

→ Wet Ingredients

01 - 1 cup mashed ripe bananas (approximately 2 large bananas)
02 - 1/2 cup sourdough discard, unfed and at room temperature
03 - 1/2 cup unsalted butter, melted and cooled
04 - 2 large eggs, at room temperature
05 - 1/2 cup whole milk, at room temperature
06 - 1 teaspoon vanilla extract

→ Dry Ingredients

07 - 1 3/4 cups all-purpose flour
08 - 3/4 cup granulated sugar
09 - 1 teaspoon baking soda
10 - 1/2 teaspoon baking powder
11 - 1/2 teaspoon salt
12 - 1 teaspoon ground cinnamon

→ Mix-ins

13 - 3/4 cup walnuts, chopped and lightly toasted

→ Brown Sugar Crust

14 - 1/4 cup light brown sugar, packed
15 - 1 tablespoon unsalted butter, melted
16 - 1/2 teaspoon ground cinnamon

# Method:

01 - Preheat oven to 350°F. Line a 9x5-inch loaf pan with parchment paper or grease thoroughly.
02 - In a large mixing bowl, whisk together mashed bananas, sourdough discard, melted butter, eggs, milk, and vanilla extract until smooth and well combined.
03 - In a separate bowl, whisk together flour, granulated sugar, baking soda, baking powder, salt, and cinnamon.
04 - Add dry ingredient mixture to wet ingredients. Stir gently with a spatula until just combined; avoid overmixing.
05 - Fold toasted walnuts into the batter using a spatula.
06 - Pour batter into prepared loaf pan and smooth the top surface evenly.
07 - In a small bowl, mix light brown sugar, melted butter, and cinnamon. Sprinkle mixture evenly over batter surface.
08 - Bake for 50 to 60 minutes, or until a toothpick inserted into the center emerges clean.
09 - Allow bread to cool in pan for 15 minutes, then transfer to wire cooling rack to cool completely before slicing.

# Expert Advice:

01 -
  • The sourdough discard adds a subtle tang that makes the banana sweetness taste less one-note and more complex.
  • That brown sugar crust cracks beautifully on top and gives you something crispy to bite into, which feels a bit luxurious for weekday breakfast.
  • It's genuinely hard to mess up, which means even if you're new to baking, this loaf will turn out moist and delicious.
02 -
  • Don't skip cooling the melted butter before mixing it in—warm butter can cook the eggs, and you'll end up with a gritty texture instead of moist and tender.
  • Your sourdough discard really does need to be unfed and at room temperature; cold or overly fed discard either won't activate properly or will add too much yeast flavor and throw off your rise.
03 -
  • If your sourdough discard is cold from the fridge, let it sit out for 15 minutes before mixing so it blends smoothly and doesn't create cold lumps in your batter.
  • Toast your walnuts in a dry skillet over medium heat for about three minutes, shaking the pan occasionally, until they smell deeply nutty—this step transforms them from ordinary to the thing people ask about.
Return