This is hands-down the best sourdough zucchini bread made with sourdough starter discard! It's lightly sweetened, with a touch of cinnamon and has an added crunch from chopped walnuts.

If you've got extra zucchini and sourdough starter discard, you've got to make this sourdough zucchini bread. In fact, bake a few loaves to put in the freezer for later!
Just like our recipe for sourdough pumpkin bread and sourdough banana bread, it couldn't be easier to make and you'll love how tender and moist it is.
We love whipping up recipes to utilize sourdough discard because it helps you to cut down on food waste and add another layer of flavor to the quick-bread.
Looking to sneak more veggies into your diet? This is an easy and delicious way to get the family to eat more veggies!
This lightly sweetened quick bread can be enjoyed morning, noon or night.

What you'll need
- fresh zucchini: Because the moisture in each zucchini varies so much, we developed this recipe with grated zucchini that has had as much moisture removed as possible. This will help to produce consistent results every time you bake this quick bread.
- light brown sugar, eggs, sourdough starter, vanilla extract, oil: One of the great things about this recipe is that you don't have to use an electric mixer. The ingredients are easy to mix with a spatula.

- flour, baking soda, baking powder, salt, cinnamon, chopped walnuts: The dry ingredients are whisked together in a separate bowl to make it easier to incorporate them into the wet ingredients, without over-mixing.

Step by step instructions
Step 1: Preheat your oven to 350°F (176°C) and lightly grease a 9" x 5" baking pan.
Step 2: Grate the zucchini and squeeze it to release any extra moisture. Leave the zucchini in a colander while you mix the remaining ingredients.

Step 3: Mix the dry ingredients together in a small bowl and set aside.

Step 4: In a large mixing bowl, combine the wet ingredients and stir until the mixture is smooth. Add the dry ingredients to the wet ingredients and stir until combined. Give the zucchini one last squeeze and stir it into the batter.

Step 5: Pour the batter into a greased 9” x 5” baking dish and bake at 350°F (176°C) for 55-60 minutes or until a toothpick inserted into the center comes out clean.
NOTE: The batter can be cold fermented in the fridge overnight after it has been mixed and poured into the baking dish. Keep it covered until you are ready to bake.

Step 6: Let the zucchini bread cool for 15 minutes. Run a butter knife around the edges to release them from the dish and transfer the bread to a cooling rack.
Enjoy warm or at room temperature.

How to store and freeze
- To store: Allow the sourdough zucchini bread to cool completely. Cover and store leftover bread at room temperature for up to 1-2 days or in the refrigerator for up to 7 days.
- To freeze: Wrap the cooled loaf in a layer of plastic wrap and then a layer of aluminum foil. Freeze up to 3 months.
- To thaw: Allow to thaw overnight in the refrigerator and bring to room temperature before slicing and serving.

Recommended kitchen tools
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- 9" x 5" baking dish (affiliate link)
- mixing bowls (affiliate link)
Simple sourdough discard recipes
We love sharing recipes that utilize discard. Browse through our sourdough discard recipes for a little baking inspiration. Here are just a few!

Sourdough Zucchini Bread
EQUIPMENT
- 9 x 5 inch loaf pan
INGREDIENTS
Dry Ingredients
- 2 cups (240 g) all-purpose flour
- 2 teaspoons baking powder
- ½ teaspoon baking soda
- 1 teaspoon (5 g) fine sea salt
- 2 teaspoons ground cinnamon
- ½ cup (60 g) chopped walnuts
Wet Ingredients
- 1 cup (220 g) light brown sugar
- 2 large eggs
- ½ cup (125 g) sourdough starter discard
- 2 teaspoons (10 g) vanilla extract
- ½ cup (109 g) vegetable oil
- 1 ¾ cups (220 g) grated zucchini (squeeze out excess liquid)
INSTRUCTIONS
- Preheat oven to 350°F (176°C) and lightly grease a 9" x 5" loaf pan.
- Grate the zucchini using the large holes of a cheese grater. Place it in a colander and squeeze out excess moisture. Leave the zucchini in the colander while you mix the remaining ingredients.
- In a large bowl, whisk together the flour, baking powder, baking soda, salt, cinnamon and chopped walnuts. Set aside.
- In a separate bowl, mix the light brown sugar, eggs, sourdough starter discard, vanilla extract and oil with a spatula until smooth. Pour the dry ingredients into the wet ingredients and mix until just combined. Stir in the grated zucchini.
- Pour the batter into the greased baking pan and bake for 55-60 minutes, or until a toothpick inserted in the center comes out clean. (See notes)
- Let the bread cool for 10-15 minutes before transferring it to a cooling rack. Slice and serve.
NOTES
- The batter can be cold fermented in the fridge overnight after it has been mixed and poured into the baking dish. Keep it covered until you are ready to bake.
- To store: Allow the bread to cool completely. Cover and store leftover bread at room temperature for up to 1-2 days or in the refrigerator for up to 7 days.
- To freeze: Wrap the cooled loaf in a layer of plastic wrap and then a layer of aluminum foil. Freeze up to 3 months.
- To thaw: Allow to thaw overnight in the refrigerator and bring to room temperature before slicing and serving.
Cheryl says
I have shredded zucchini in my freezer. Can this be used for this recipe? Thanks!
Amy says
Yes it can. I would allow it to thaw and squeeze excess moisture before using in the batter!