We’re about to head into the height of zucchini season, which is just one of the many reasons you’ll adore this Chocolate Zucchini Cake.
I love getting fresh zucchini from the farmer’s market all summer long. It’s one of those veggies that’s so easy to cook and bake with. You can find a million ways to get creative whether you’re going savory or sweet. And it doesn’t take nearly an hour to cook like root veggies.
Adding zucchini to cake happens to be one of my favorite ways to use the stuff. I also enjoy a good zucchini bread, like this Lemon Yogurt Zucchini Bread.
I love snack cakes like this recipe because they’re just one layer, and there’s no assembly or decorating required. They’re also super easy to transport. You don’t even need an electric mixer for the batter or the icing here!
That makes this recipe perfect for bringing to a summer potluck or BBQ. Especially if you have an abundance of zucchini to use up!
I find many chocolate zucchini cakes to be kind of bland and a little dry. Read my tips below for getting a super rich and fudgy cake with tons of chocolate flavor.
This might just become your new favorite zucchini recipe!
How to Make Moist Chocolate Zucchini Cake
The Best Cocoa Powder for Chocolate Cake
Cocoa powder lends more chocolate flavor than melted chocolate. But it can also zap some moisture, so read my tips below for how to make sure your cake is nice and tender and moist. This recipe uses natural unsweetened cocoa powder (not Dutch process cocoa powder). Learn more about cocoa powder here.
For best results, weigh your cocoa powder and flour to ensure you don’t over-measure. This will result in a dry cake. If you don’t have a digital kitchen scale, then use the spoon-and-level method.
How to Shred Zucchini for Cake (IMPORTANT!)
To avoid gummy, dense, or unbaked Chocolate Zucchini Cake, it’s important to remove as much excess water from the zucchini as possible.
- Start by washing the zucchini and trimming the ends. Grate using the big holes of a box grater. Scoop up the shredded zucchini and place in a strainer or colander. Move on to prepare the rest of the ingredients and batter for the recipe.
- Once you’re ready to add in the zucchini, wrap it in a clean towel or paper towels and give it a very tight squeeze with your hands to wring out excess water. Do this a few times. If your hands aren’t quite strong enough, you can also press the zucchini inside a potato ricer or hand-held citrus squeezer. This is super effective at getting rid of water.
- Once you fold in the zucchini to the batter, stir gently until JUST combined. Over-mixing can cause a tough or gummy texture.
Why Use Butter AND Oil in a Cake?
- I find this provides the best of both worlds.
- You get the wonderful flavor from the butter and the moist texture from the oil.
- This is because oil is a liquid at room temperature so it gives your palate the sensation of moisture.
- Learn more about Butter vs. Oil in Baking here.
How to Bake a Moist & Fudgy Chocolate Cake
- In addition to the tips above, using ingredients like brown sugar, full-fat sour cream, and an extra egg yolk all help to add richness and moisture to this cake.
- That’s because these ingredients both tenderize and draw and hold onto moisture.
- You can learn more about how baking ingredients work in my Magic of Baking online class.
Can I Substitute the Sour Cream?
You can use full-fat plain yogurt instead!
What Type of Chocolate Chips Should I Use?
I used semi-sweet chocolate chips, but you could experiment with milk chocolate chips, mini chocolate chips, or even white chocolate chips, if you prefer.
Is it Better to Bake a Cake in a Glass or Metal Pan?
- This recipe is best baked in an 8-inch metal baking pan.
- Metal conducts heat more quickly and efficiently than glass or ceramic so you won’t have any issues with an under-baked center.
- If you must use glass or ceramic, reduce the baking temperature to 325°F and increase the baking time by 5 to 10 minutes.
- Learn more about Glass vs. Metal Baking Pans in my article here.
Frosting for Zucchini Cake
I used a simple icing for this Chocolate Zucchini Cake recipe, but you could also use my cream cheese frosting or even this chocolate frosting.
Can I Double this Recipe?
Yes! Double all ingredients, bake in a 9 by 13-inch pan, and add about 5 to 10 minutes to the baking time. If using glass, see note above.
How Long Does Chocolate Zucchini Cake Last?
This Zucchini Cake can be stored in an airtight container at room temperature for up to 4 days.
Can You Freeze Chocolate Zucchini Cake?
- Freeze individual slices on parchment paper for about 15-30 minutes, then wrap each in plastic wrap and place in an airtight container.
- Defrost in the fridge or on the counter and let come to room temperature before enjoying.
- I recommend freezing the cake unfrosted.
More Chocolate Cake Recipes
For the cake:
-
1
cup
plus 2 tablespoons (143 grams) all-purpose flour,
measured correctly
-
1/2
cup
(43 grams) unsweetened cocoa,
measured correctly
-
1
cup
(200 grams) light brown sugar
-
1
teaspoon
salt
-
1
teaspoon
baking soda
-
4
tablespoons
(57 grams) unsalted butter,
melted
-
1/4
cup
fresh vegetable oil
-
1/2
cup
(120 grams) full fat sour cream or plain whole milk yogurt,
at room temperature
-
2
large eggs plus 1 egg yolk,
at room temperature
-
2
teaspoons
vanilla extract
-
1
cup
(136 grams) shredded zucchini,
from about 1 medium zucchini
-
1
cup
(170 grams) semisweet chocolate chips
For the icing:
-
1/2
cup
(63 grams) powdered sugar,
sifted
-
1
tablespoon
milk
Make the cake:
-
Preheat the oven to 350°F. Line an 8 by 8-inch metal baking pan* with parchment paper then spray with nonstick cooking spray.
-
In a large bowl, whisk together the flour, cocoa, sugar, salt, and baking soda.
-
In a small bowl, whisk together the melted butter, oil, sour cream, eggs, egg yolk, and vanilla extract.
-
Make a well in the center of the dry ingredients and pour in the wet ingredients. Stir until a few streaks of flour remain. Squeeze out any additional moisture from the shredded zucchini before adding to the batter (see recipe post for tips on reducing excess moisture, which will create a gummy cake texture). Add in the chocolate chips. Stir until just barely combined.
-
Pour the batter into the prepared pan and bake for 30 minutes or until a toothpick or cake tester comes out clean. If your cake sinks slightly in the middle, that's normal because it's so moist and rich!
-
Let cool completely.
Make the frosting:
-
In a medium bowl, stir together the sugar and milk with a fork until smooth and thick but pourable. Drizzle all over the cake. Let set before serving.
-
Cake can be stored in an airtight container at room temperature for up to 4 days.
* If using a glass pan, bake at 325°F for 35 to 40 minutes, or until a toothpick or cake tester comes out clean.
Photos by Ashley McLaughlin.
THE BEST! The zucchini disappears and it turns into a rich, moist, chocolate cake. And super easy to make. I would recommend to anyone, and will be making this again and again.
YAY! So glad to hear it, Sarah! Thanks for the rave review 🙂
Hi! This was one of my favorite recipes last summer, but now I can’t recall how I measured the zucchini. Should we have 1 cup before removing the moisture or after? I would imagine 1 cup compressed will be much more than a cup to start with. Thanks!
Hi Nina! You’ll want to start out with 1 cup of just shredded zucchini. You’ll squeeze the moisture out of the shredded zucchini right before adding it to the batter. Enjoy your cake! 🙂
Very delicious cake! Perfectly moist, not too dense or airy. I added a little bit of instant coffee powder to the wet ingredients to elevate the chocolate. The overall taste and texture reminds me of the giant chocolate muffins from Costco.
So happy you enjoyed this cake, Melinda!
Hey, I just have a quick question ^^
How many grams (or ml) are 1/4 cup of vegetable oil? I live in Europe and we don’t use cups here and on the internet are so many different answers, so I’m kinda unsure about that
There’s about 224 grams of oil in 1 cup, so about 56 grams should be perfect 🙂
Hi sweetie
I just have a question if I may
how I can make chocolate chip cookies less sweet, but keep the same texture?
Can you give me a recipe or a way to do that
Thank you
Your best bet is to probably search for low sugar chocolate chip cookie recipes on Google. I don’t ever recommend reducing the sugar in regular cookie recipes as it can alter the chemistry of them!
Delicious! Super moist and chocolates. Thank you!
I froze several bags of shredded zucchini, would I follow the same steps after it defrosts? Wringing it out? I would assume so but wanted to double check in case it adds additional moisture! Thank you!
I haven’t tried that, but I’d recommend making sure it’s very well drained! Other than that, it should be fine, let me know how it goes!
This cake is delicious & so easy. I put chocolate ganache & sprinkles on top. Will make this again
Yay! So thrilled you enjoyed this recipe.
Moist and delicious! It came out of the oven about 30 minutes ago. I couldn’t wait for it to cool completely to eat a piece. I definitely will make it again.
Hey this is super important , please answer as soon as you can. How many calories are there, because I need to know soon, I am needing this recipe for a thing tomorrow and would like to know before then,
Thank you.
The typical chocolate zucchini cake I’ve made for years was just NOT chocolatey enough. This one is FABULOUS! Since I live just west of Denver at an altitude of 5,459′, I made some adjustments. I upped the flour to 151 grams, decreased the sugar by 1 TAB, used 3 full eggs, and increased the temp to 365 degrees. It took about 38 minutes to cook. It was so yummy with just a bit of powdered sugar on top.
I did have a question. Since I used a very large zucchini, I spooned out the seeds before I grated. When do you weigh the zucchini…before or after you press out the moisture?
Can I freeze the chocolate zukini cake and hoe long thanks..
Fabulous so good. Best cake I’ve ever made..1 substitution. Greek plan yogurt for sour cream. And chocolate cream cheese icing. Oh so good!!!
You’d think this cake would be heavy and dense, it’s not at all. It’s somehow stays light and has great flavor and texture. I did add a couple of tsp of instant expresso powder to it, subbed walnuts for choc chips and used a melted a chocolate and chili bar for the icing. Superb with or without these additions I’m sure.
This is my third time making this cake in the last month. The first time I was supposed to give a piece to my uncle down the street and I ate it all before it got to him. The second time I made it for a party and the whole thing was gone before I could even get a slice. This time it’s allll for me and my fiancé. It is SO delicious and the icing glaze just makes it that much better. I call it our healthy chocolate cake so I’m sure we will use that excuse to make it a bunch more times.
Trying ur chocolate Zucchini cake! I’ll let you know how it goes
Delicious and moist. The recipe was easy to follow.
Turned out perfect. Doubled the recipe and added 5 eggs instead of adding egg yolks. Super moist but not dense. My family loved it!
The BEST. It’s everything she said it was! We put vanilla ice cream on it!ya
So moist and tender and mouthwatering good!
1 cup shredded zucchini before wrenching it or 1 cup shredded zucchini after removing the water?
So easy and delicious! I sprinkled a few extra chocolate chips on top before baking.
Delicious, moist, decadent and chocolatey! Another winning recipe from Tessa and perfect timing with all the zucchini’s in season!
This cake is so moist and delicious!! I just had to have a second piece! Quick and easy to make. I’ll be making this again!
This is the fourth time I’ve made the recipe. Super easy and extremely DELICIOUS! I usually make it without the frosting and it’s just as amazing as with the frosting! I store it in an lidded container in the refrigerator to keep longer and a quick reheat in the microwave makes this gooey delicious chocolate cake amazing with a cold glass of milk!
It was very moist and I liked the bits of chocolate chips throughout! Very delicious!
Perfectly moist and rich chocolate flavor! Delicious and would never know zucchini is in the cake 🙂 Definitely recommend the recipe to all chocolate lovers!
This recipe is fantastic! So easy to make and it tastes like a reich and moist chocolate cake. And bonus: my family didn’t even know it had a full zucchini in the cake. Hehe!
Made this tonight, moist, fluffy, chocolaty deliciousness!
Ah, this was amazing! So moist and delicious! My chocolate-cake-hating mom loved this cake, and that’s saying a lot! Thanks so much Tessa for the recipe!
OMG so delicious! Super moist and rich flavour!
Delicious cake! And so easy to make, thanks to the detailed instructions and tips!
This recipe is double perfect: easy to make and tastes amazing!
I baked it virtually for my brother’s birthday and physically for my friend’s birthday on the same day. Decided to join the challenge too!!
Its choco zucchini but when you eat it you d be like: “where is the zucchini? Are you sure ?”
Soo good.. thank you #handletheheat
So moist! I’m not a chocolate cake fan, but this is delicious!
Delicious and very moist!
Used a whole egg instead just the egg yolk and dusted with powdered sugar as I don’t like icing. Very rich and chocolatey!
Absolutely LOVE this recipe! This is the first time I have ever used zucchini in baking and thus definitely won’t be the last. So yummy and moist.
I’ve commented on this wonderful cake at least four times. This is becoming burdensome!
The best Chocolate Chip Zucchini Cake I’ve ever made! Moist and delicious! Good work Tessa!
Awesome! I had to hurry to take the pictures ’cause I had family pestering me for a slice. This is another in the line of recipes that Tessa nailed. Go girl!
This recipe is so delicious! It’s moist, chocolaty, and so easy to make!
Made this cake recently and it was super rich and moist, extra chocolatey, and has a hidden taste of zucchini and that can trick anyone! 10/10 quick and easy recipe that I highly recommend making.
First time using zucchini on a sweet recipe and I loved the result. Super moist and delicious! I don’t have a square metal pan, so I used a round ceramic pan, and following Tessa’s instructions it still turned out great.
SO moist and delicious! A great way to use my zucchini’s from my garden. I made it twice in one month to share with my family!
Perfect amount of zucchini and you definitely need a glass of milk with the chocolatey decadence!
Super easy, super moist, super delicious! I used a potato ricer for drying out the zucchini and it worked perfectly. What a great way to use up extra zucchini this time of year. Will definitely make again – maybe with a little squeeze of lemon juice in the frosting too!
I’ve made chocolate zucchini cake & zucchini brownies before, but this recipe really impressed me. It doesn’t really help much in terms of using up an abundance of zucchini, but it’s so moist & fluffy, yet rich & delicious, the small amount of zucchini used truly does seem to disappear. Speaking of disappearing, this cake was gone so fast, I wish I had made a double recipe!
Can you use a glass pan?
Yes Linda you can just lower the temp to 325 and add 5 to 10 extra minutes..
Delicious and so much chocolate!
This cake is moist and delicious! I would start with less milk in the icing, however. It kind of disappeared into the cake when it dried.
I doubled this recipe in order to make it in a 9 x 13 cake pan. The cake is very bitter and dense. After looking at other recipes, the amount of cocoa in this recipe is excessive, not sure why it is so dense.
Very tasty!
Quick, perfectly moist and sooooo chocolatey. Will make again but with less milk in the 1/2 cup of confectioners sugar for topping.
Very moist and fudgy. It tastes wonderful just what one needs during a chocolate craving. Will make again, and again, and again.
This recipe was very easy and delicious! It’s very chocolatey and rich, almost like a cross between a brownie in taste and a cake in texture. It was excellent with ice cream on top.
What a delicious chocolate zucchini cake and so easy to make! You don’t even have to use a mixer.
My family is in love with it.
What a delicious chocolate Zucchini cake and so easy to make! You don’t even have to use a mixer.
Made this recipe using well-drained frozen zucchini and it turned out fabulous! My kids loved it!
Rich, chocolatey, and delicious! I loved how quick and easy this was!
Rich, chocolatey and delicious! I loved how quick and easy this was!