Got garden zucchini? Turn it into the most wholesome and delicious sourdough muffins!

These sourdough zucchini muffins make the best breakfast… They’re packed with zucchini, the benefits of sourdough, and are perfectly moist! Just like my Fluffy Sourdough Pancakes and Crispy Sourdough Waffles, to the comforting Sausage Gravy and Biscuits… I’ve got your mornings covered!
Long Fermentation (Why You May Want to Try It!)
Long fermentation might sound fancy, it’s actually very simple, and optional but recommended for these muffins, if you have the time.
Why bother letting your batter ferment for 8-12 hours (overnight)? It gives your sourdough starter more time to work its magic, truly transforming your muffins! Here’s the scoop on the benefits:
- Deeper Flavor: Your muffins get an even richer, more complex taste as the sourdough develops incredible flavor.
- Lovely Texture: While baking soda and powder do the heavy lifting for rise, fermentation really contributes to a nice tender crumb. 😉

How it Works (and Why Timing Matters!)
If you long ferment, simply mix your wet and dry ingredients (holding back the baking soda and baking powder!), fold in the zucchini, cover, and let it sit. You might notice slight bubbling—that’s your sourdough doing its thing!
Do NOT add the baking soda and baking powder until after the fermentation. The baking soda needs acid to react and create lift. During the long ferment, your sourdough produces more of that beneficial acid. Adding the baking soda, and baking powder right before baking gives it plenty to react with, so your muffins have the best rise and texture. 😉

Key Ingredients
Let’s chat about the stars of the show for these delicious sourdough zucchini muffins! While every ingredient plays a role, these are the ones that really make the magic happen. Don’t worry, we’ve got some friendly tips and easy swaps for you too!
Active Sourdough Starter: This is truly the heart of our recipe! “Active” means your starter is bubbly, fed, and ready to go… Ideally, it should have been fed 4-12 hours before you plan to bake. A lively starter is key for flavor and for helping with that tender crumb, especially if you opt for the long fermentation!
Zucchini: Of course! You’ll need about 1-2 medium zucchini to get your 2 cups.

Flour (Whole Wheat, Einkorn, OR Unbleached All-Purpose):
Whole Wheat or Einkorn: These will give your muffins a more rustic, nutty flavor and a denser, heartier texture. Plus, they add extra fiber – bonus!
Unbleached All-Purpose Flour: If you prefer a lighter, softer muffin, or if that’s just what you have in your pantry, all-purpose flour is a perfectly fantastic choice. It’s reliable and will give you a classic muffin texture. Feel free to mix and match too!

Baking Soda & Baking Powder: These are your leavening agents, they that gives your muffins that wonderful rise! They work together, especially with the acidity from the sourdough. Remember our note about when to add them – it’s important!
Oil (Olive Oil or Avocado Oil): We’re using oil here for a super moist and tender muffin. Both olive and avocado oil are great choices because they have a mild flavor that won’t overpower the zucchini and cinnamon, plus they add to that lovely soft texture. If you only have another neutral-flavored oil like melted coconut oil (liquid form), that would work in a pinch, but I prefer olive or avocado.
Eggs: These bind everything together, add moisture, and add richness and structure of your muffins. They’re pretty essential!

I wanna know know what YOU think… Please leave a review!

Sourdough Zucchini Muffins with Crumble Topping
Ingredients
- 2 cups flour whole wheat, einkorn, OR unbleached all-purpose flour
- ¾ cup granulated sugar pure cane sugar recommended
- ¾ cup ground flax seed
- 1 teaspoon salt
- 1 teaspoon baking soda See Note on Fermentation below
- 1 teaspoon baking powder
- 2 cups grated zucchini
- ½ cup active sourdough starter
- 1 teaspoon vanilla extract
- 1 teaspoon cinnamon powder
- 2 large eggs
- ⅔ cup olive oil or avocado oil
For the Crumble Topping:
- ½ cup granulated sugar
- ⅓ cup flour einkorn or all-purpose
- ¼ cup cold butter cubed
- 1 ½ teaspoons ground cinnamon
Instructions
Combine Dry Ingredients (Except Baking Soda and powder, if Fermenting):
- In a large bowl, whisk together the 2 cups flour, ¾ cup granulated sugar, ground flax seed, salt, 1 teaspoon baking powder, 1 teaspoon baking powder, and 1 teaspoon cinnamon powder. If you plan to long ferment, do NOT add the baking soda and powder yet.
Mix Wet Ingredients:
- In a separate medium bowl, whisk together the active sourdough starter, vanilla extract, eggs, and ⅔ cup olive oil until well combined.
Combine Wet and Dry:
- Pour the wet ingredients into the dry ingredients and mix until just combined. Be careful not to overmix; a few lumps are fine.
Add Zucchini:
- Gently fold in the grated zucchini.
- Optional Long Fermentation (for enhanced flavor and digestibility):
- If you are long fermenting: Cover the bowl with plastic wrap or a clean kitchen towel and let it sit at room temperature for 8-12 hours, or overnight.
- If you are NOT long fermenting: Proceed to the next step.
Incorporate Baking Soda (Crucial Step):
- If you long fermented: After the fermentation period, stir in the 1 teaspoon of baking soda and 1 teaspoon baking powder and stir thoroughly. This will react with the acids in the sourdough to create a lighter texture.
- If you did NOT long ferment: Add the 1 teaspoon of baking soda and baking powder along with the other dry ingredients in step 1.
Prepare the Crumble Topping:
- In a small bowl, combine the ½ cup granulated sugar, ⅓ cup flour, and 1 ½ teaspoons ground cinnamon. Add the cold, cubed butter. Use your fingertips or a pastry blender to cut the butter into the dry ingredients until the mixture resembles coarse crumbs.
Bake the Muffins:
- Preheat your oven to 375°F (190°C). Line a 12-cup muffin tin with paper liners or grease it well.
- Divide the muffin batter evenly among the 12 muffin cups.
- Generously sprinkle the crumble topping over each muffin.
- Bake for 20-25 minutes, or until a wooden skewer or toothpick inserted into the center of a muffin comes out with only a few moist crumbs attached.
- Let the muffins cool in the muffin tin for a few minutes before transferring them to a wire rack to cool completely.
Notes
Nutrition

About Juliea
Juliea Huffaker is the creator of Farmhouse Harvest, and dedicated to teaching from-scratch cooking, sourdough baking, gardening, and food preservation. With over 25 years of hands-on experience she has preserved hundreds of jars of produce, mastered the art of meats and sourdough baking, and nurtured a thriving organic garden. Her recipes and articles have been featured across the web. And she’s passionate about inspiring others to embrace a simpler, self-sufficient life style.








