Lemon Blueberry Zucchini Cake with Lemon Frosting

OMG it’s the cake you’ve been waiting for: LEMON BLUEBERRY ZUCCHINI CAKE!

I posted a video of this cake over on my Instagram page a few weeks ago and ya’ll went crazy for it. I mean I knew AK readers were lemon lovers, but this really took it to the next level — and for good reason too…THIS CAKE IS SIMPLY AMAZING.

It’s made in one bowl, and baked in one pan (no need to layer!). And, you’d never guess that that it’s healthier, gluten free or made with zucchini! I’m telling you, this healthy lemon blueberry cake is next level.

piece of blueberry zucchini cake next to blueberries

Lemon blueberry zucchini cake ingredients

This delicious gluten free blueberry zucchini cake is made with fresh, healthy produce like zucchini, lemons and blueberries, and is gluten free thanks to almond & oat flour. Just wait until you try that lemon buttercream. YUM. It’s easily dairy free, too! Here’s everything you’ll need:

Zucchini: shredded zucchini adds the perfect amount of moisture to this cake so that we don’t have to use any oil. Be sure to measure the shredded zucchini, then squeeze it of excess moisture.
Eggs: you’ll need two eggs in this cake recipe.
Honey: this healthy blueberry zucchini cake is naturally sweetened with honey! You could also use pure maple syrup if you prefer but I love the honey + lemon combo.
Lemon: we’re using both lemon juice and lemon zest for the ultimate lemon flavor.
Almond extract: for that delicious lemon cake flavor.
Almond flour: to keep this cake gluten free we’re using fine, blanched almond flour. I cannot recommend a substitute for the almond flour because it provides fat and texture for the recipe.
Gluten free oat flour: we’re also mixing the almond flour with gluten free oat flour. It’s one of my favorite combos! See below for how to easily make it yourself! You could also try a 1:1 gluten free flour or regular all purpose flour, but please note that I haven’t tested this myself.
Baking soda & salt: to bake this cake up properly.
Blueberries: pile in fresh, juicy blueberries. Yes, please!
For the frosting: the lemon buttercream is made up of butter (or vegan butter), powdered sugar, lemon juice & lemon zest.

unbaked gluten free lemon blueberry zucchini cake in a square pan

How to make homemade oat flour

You can easily make your own gluten free oat flour by simply placing gluten free oats into a blender and blending or pulsing until they’re smooth and resemble flour. This is a super easy & affordable option. Be sure to measure out 1 cup of your oat flour after making it! It’s also important to make sure your oat flour is VERY fine. If you want to keep this cake gluten free, I suggest using gluten free oats to make your oat flour.

unfrosted healthy blueberry zucchini cake in a square pan

Tips for making this gluten free blueberry zucchini cake

Squeeze out ALL of the extra moisture from your zucchini. This will ensure that the zucchini cake bakes up well and isn’t too moist. First measure the zucchini, then squeeze it of excess moisture.
Zest your lemons before juicing them. This makes it much easier to get all of the zest from the rind!
Toss your blueberries in a bit of oat flour before mixing them into the batter. This will ensure that the cake doesn’t turn completely blue and that the blueberries don’t fall to the bottom.
To make this zucchini cake dairy free simply use a vegan buttery stick in the frosting (or swap for your favorite dairy free frosting & add a little lemon zest + lemon juice — we love Simple Mills frosting!)

lemon blueberry zucchini cake topped with lemon frosting and blueberries

How to store lemon blueberry zucchini cake

This gluten free lemon blueberry zucchini cake can actually be made 1-2 days ahead of time! You can also store it after you’ve frosted the cake, too.

How to store blueberry zucchini cake: feel free to keep the cake at room temp for one day. After that I recommend storing the cake covered in the refrigerator for up to 5 days.

To freeze: feel free to freeze this cake either frosted or unfrosted for up to 2 months. I recommend freezing it unfrosted for best results. Wrap the cake in plastic wrap, then aluminum foil and then placing the cake in a zip-top freezer bag. When you’re ready to serve it, simply thaw it in the refrigerator overnight, let the cake come to room temperature, frost it and serve it.

slice of gluten free lemon blueberry zucchini cake on a plate

AK Zucchini Week GIVEAWAY

We’re giving away one Dinner for 4 Set from Our Place to one lucky winner! Here’s how to enter:

Share a photo of any AK zucchini recipe you make on your Instagram feed with the hashtag #AKZucchiniWeek (your profile must be public in order for us to see it), or add it to our private Facebook Group.
The more you post & share your recipe photos, the greater chance you have to win!
Winner will be announced on Monday, 8/10 and notified via DM on Instagram or in the Facebook group. Must be 18 or older, USA only.

See how to make the lemon blueberry zucchini cake

I hope you love this easy lemon blueberry zucchini cake recipe! If you make it be sure to leave a comment and a rating so I know how you liked it. Stay tuned for more zucchini recipes all week, xo!

Lemon Blueberry Zucchini Cake with Lemon Frosting

Gorgeous lemon blueberry zucchini cake bursting with juicy blueberries and topped with a luscious lemon buttercream frosting. This easy, gluten free blueberry zucchini cake is made with a mix of oat and almond flour and naturally sweetened with honey. A delicious snacking cake perfect for using summer produce!

Wet ingredients:
1
cup
shredded zucchini (from 1 medium zucchini)
2
eggs
½
cup
honey
zest from 2 lemons
2
tablespoons
fresh lemon juice
1/2
teaspoon
almond extract
Dry ingredients:
1 ½
cup
packed blanched fine almond flour
¾
cup
gluten free oat flour
1
teaspoon
baking soda
1/4
teaspoon
salt
For the blueberries:
1
heaping cup fresh blueberries
2
tablespoons
gluten free oat flour
For the lemon frosting:
½
cup
butter (or sub vegan buttery stick), at room temperature
1
cup
powdered sugar
1
tablespoon
fresh lemon juice
1
teaspoon
lemon zest
To garnish:
Extra blueberries for sprinkling on top

Preheat the oven to 350 degrees F. Line an 8×8 inch square pan with parchment paper and spray with nonstick cooking spray. Set aside.
First, measure out 1 cup of shredded zucchini, then place shredded zucchini in a paper towel or cheese cloth and squeeze out all of the moisture/water. This is very important!
Add shredded zucchini, eggs, honey, lemon zest, lemon juice and almond extract to a large bowl and whisk together until well combined.
Next, add dry ingredients: almond flour, oat flour, baking soda and salt. Mix together with a wooden spoon until well combined.
In a separate medium bowl, toss blueberries together with 2 tablespoons of oat flour. (This is to prevent the blueberries from sinking to the bottom of the cake while baking.) Fold coated blueberries into the batter.
Pour batter into the prepared pan. Bake for 30-35 minutes or until a tester comes out clean. Allow the cake to cool completely on a wire rack before frosting. I know this is difficult but it’s critical (otherwise the frosting will melt and become a gooey mess!)
Make the frosting: beat together butter, powdered sugar, lemon juice and lemon zest together on high with a hand mixer or in the bowl of an electric mixer until smooth. Spread frosting over cooled cake. Garnish with a few blueberries. Cut into 9 slices and enjoy!

I do not recommend a substitution for almond flour, as that’s the only ‘fat’ in this recipe and helps to keep the cake moist and retain its texture.

If you’re looking for an oat flour sub, I think regular flour or GF 1:1 flour would work well, but haven’t tested it myself.

Cake can be made a day ahead of time. After a day, the cake should be transferred and stored in the fridge.

Nutrition

Servings: 9 servings

Serving size: 1 slice (with frosting)

Calories: 376kcal

Fat: 21.3g

Saturated fat: 7.3g

Carbohydrates: 44.6g

Fiber: 3.6g

Sugar: 30.1g