This moist sour cream zucchini coffee cake is a lovely summer baking idea with a touch of cozy fall flavor. It has a tender, spongy cake base, a crisp streusel topping, and a simple sweet icing. The zucchini blends in so well you only notice tiny green speckles that add charm and extra moisture.

I look forward to summer partly for the treats that come with it — zucchini shows up in lots of my baking during the season. This sour cream zucchini coffee cake is one of my favorites. It tastes like a classic spiced coffee cake but feels lighter with the fresh zucchini folded in. It’s not a health food, but the zucchini does add moisture and a little nutritional boost to an indulgent dessert, which feels like a win.
You truly won’t taste zucchini; it simply keeps the cake incredibly soft and tender. It’s perfect with a cup of coffee, on a rainy summer afternoon, or whenever you want a comforting, textured treat.

What makes this sour cream zucchini cake so MOIST?
I recently tested this recipe multiple times and it consistently stayed moist, even when left uncovered overnight by accident. A few key elements combine to produce that tender, lasting texture:
• Zucchini: Fresh shredded zucchini adds plenty of moisture. Unlike many zucchini-baked goods that call for squeezing out liquid, I skip that step here. Leaving some moisture in keeps the cake softer.
• Sour cream: Sour cream contributes richness and a velvet crumb. Its acidity also helps with lift, and because it’s not overly wet, the batter holds together well.
• Oil: Using oil rather than butter helps the cake retain moisture longer. Oil also makes the batter easier to work with because you don’t need to bring ingredients to room temperature.

How to make sour cream zucchini coffee cake
1. Mix the streusel ingredients until crumbly and set aside.
2. Grate the zucchini and set it aside.


3. Whisk the wet ingredients together until smooth.
4. Fold the shredded zucchini into the wet mixture.


5. Stir in the dry ingredients until just combined — avoid over mixing.
6. Spread the batter into your prepared pan and sprinkle the streusel on top.
7. Bake, then allow the cake to cool slightly.




8. Prepare a simple icing and drizzle it over the warm cake. Slice and serve.


Tips for making sour cream zucchini coffee cake
- Grate the zucchini correctly: Use the large side of a box grater. Zucchini is very moist, and using the fine grater can make the batter too watery.
- Measure flour carefully: Weigh flour if you can. If measuring by cups, use the spoon-and-level method: fluff the flour, spoon it into the measuring cup, then level it with a flat edge.
- Don’t over mix: Mix until ingredients are just combined. Over mixing develops gluten and can lead to a dense, dry cake.
- Bake and cool properly: Avoid overbaking. Cool the cake in the pan for about 45 minutes, then remove it. Leaving it in the hot pan too long can dry the cake out as the pan continues to radiate heat.
- Storage: Keep the cake tightly covered to retain moisture. It will last about 3 days at room temperature or up to 5 days refrigerated, though it’s usually eaten sooner.

Check out these other summer recipes
• Lemon Poppy Seed Cupcakes
• Giant Strawberry Pop Tart
• Lemon Raspberry Cake
• No-Bake Chocolate Peanut Butter Fudge Bars
If you make this recipe, please leave a comment and review — I love hearing how it turns out! Tag me on Instagram @eatsdelightfulblog so I can see your creations.
Sour Cream Zucchini Coffee Cake
No reviews
- Author: Mimi
- Total Time: 1 hour 45 minutes
- Yield: 9 slices
Description
This moist sour cream zucchini coffee cake combines a tender cake base, crunchy streusel, and a simple icing for a textured, comforting dessert. The zucchini keeps the cake soft and barely alters the flavor, so it feels like a classic coffee cake with extra moisture and charm.
Ingredients
For the streusel:
- ¾ cup (90g) all-purpose flour, spooned and leveled
- ½ cup (100g) packed brown sugar (light or dark)
- 1 teaspoon ground cinnamon
- ¼ cup (60g) unsalted butter, melted and cooled
For the zucchini cake:
- ¼ cup (60mL) vegetable oil (or a neutral oil)
- ⅓ cup (80g) full-fat sour cream
- ½ cup (100g) granulated sugar
- ½ cup (100g) packed brown sugar
- 1 large egg
- 1 teaspoon pure vanilla extract
- 1½ cups (195g) loosely packed shredded zucchini
- 1 teaspoon ground cinnamon
- 1 teaspoon baking powder
- ½ teaspoon baking soda
- ¼ teaspoon salt
- 1½ cups (180g) all-purpose flour, spooned and leveled
For the icing:
- 1 cup (130g) powdered sugar
- 1–2 tablespoons milk or water
Instructions
- Preheat the oven to 350°F (175°C). Butter an 8×8 inch pan and line the bottom and sides with parchment paper, leaving an overhang to lift the cake out later.
- Make the streusel: Combine the flour, brown sugar, cinnamon, and melted butter. Use a fork to mash everything together until crumbly. Set aside.
- Make the cake batter: In a large bowl, whisk together the oil, sour cream, granulated and brown sugars, egg, and vanilla until smooth.
- Fold the shredded zucchini into the wet ingredients.
- Stir in the cinnamon, baking powder, baking soda, salt, and flour until just combined. Do not over mix.
- Pour the batter into the prepared pan and spread evenly. Sprinkle the streusel on top.
- Bake on the center rack for 40–50 minutes, or until the top is puffed and a skewer inserted in the center comes out clean or with a few moist crumbs.
- Cool in the pan for about 45 minutes to set before removing.
- Make the icing: Whisk the powdered sugar with 1 tablespoon of milk or water until smooth. Add more liquid if needed to reach a drizzling consistency.
- Lift the cake out using the parchment overhang, transfer to a serving plate, and drizzle the icing over the slightly warm cake. Serve warm or at room temperature.
Equipment
8×8″ baking pan
Four-sided box grater
Glass measuring cups
- Prep Time: 20 minutes
- Bake Time: 40 minutes
Enjoy!