Chocolate Zucchini Cake Recipe

This fudgy, ultra-moist chocolate zucchini cake recipe is the perfect way to use up that ripe zucchini! It bakes up so moist and tender and is studded with chocolate chips. It’s so good it doesn’t even need frosting, and that means a lot coming from me.

How to Make This Fudgy Chocolate Zucchini Cake

Let’s walk through each step of this recipe to make sure it turns out as amazing as possible.

Step 1: Make the Chocolate Cake Batter

First, we tackle the chocolate cake batter! Preheat the oven to 350°F/175°C and line and grease a square 8-inch metal pan or a round 9-inch cake pan.

In a large bowl, add 1/2 cup warm water, 1/2 cup sour cream, 1/4 cup oil, 1 egg, 1 tsp vanilla, and 1 tsp instant espresso (optional). Whisk together until combined.

In a separate, medium-sized bowl, whisk together 1 cup + 2 Tbsp flour, 1 cup sugar, 1/3 cup cocoa powder, 1 tsp baking powder, 3/4 tsp baking soda, and 1/2 tsp salt.

Add the dry ingredients to the wet ingredients and mix until just combined.

Then fold in 1 1/2 cups of peeled and shredded zucchini that’s been blotted/gently dried with a paper towel and 2/3 cup of chocolate chips into the batter.

The goal of blotting the zucchini is to remove just a bit of the moisture, but not all of it! You do not want to wring out the zucchini.

Pour the batter into the prepared pan, then sprinkle the remaining 1/3 cup of chocolate chips on top of the batter.

Bake for 35-40 minutes, or until a toothpick inserted in the center comes out with a few moist crumbs. Remove the pan from the oven.

Place the pan on a wire cooling rack and let the cake cool fully in the pan. If you’re in a rush, place the whole pan in the freezer for 30 minutes to accelerate the cooling process.

This cake can be stored at room temperature for up to 3 days or in the fridge for 5 days.

Substitutions & Swaps in This Chocolate Zucchini Cake Recipe

This recipe uses quite a few ingredients, and I know you might not have them all on hand. Or if you have food allergies or restrictions, I’ve got you covered.

Below are some swaps and substitutions that you can make.

• All-Purpose Flour – This recipe turns out best with all-purpose flour. However, you can swap in a good gluten-free flour blend (like this) if needed. Just be sure to stir the batter longer than normal to help give the cake proper structure, and let the batter sit for about 20 minutes before baking it if you opt to make a gluten-free version.
• Granulated Sugar – I do not recommend reducing the amount of sugar or changing the type of sugar, as it will change the texture of the cake.
• Dark Baking Cocoa – I like to use Hershey’s brand of dark baking cocoa, but you can also use Dutch-processed cocoa or black cocoa. If you can’t find dark cocoa powder or don’t have any on hand, you can use regular unsweetened baking cocoa in its place.
• Sour cream – You can also use full-fat Greek yogurt, buttermilk, whole milk, or an alternative yogurt or milk (almond, soy, oat).
• Vegetable Oil – Any flavorless oil can be used in this recipe. Canola, vegetable, or even sunflower oil would all work great. Olive oil can be used too, but it might give the cake a slightly different flavor.
• 1 Large Egg – This recipe uses a large egg. If you have an egg allergy, you can try using a vegan egg replacer.
• Grated Zucchini – I usually use freshly grated zucchini, but you can also use frozen zucchini. Just thaw it first, then give it a gentle squeeze to remove the excess liquid (otherwise the batter can turn out too watery). You don’t need to wring it completely dry—keeping a little bit of moisture helps keep the cake tender and fudgy.
• Chocolate Chips – Any type of chocolate chip or chopped chocolate bar will work in this recipe! I prefer mini chocolate chips. You can also skip adding the additional chocolate.

Making This Chocolate Zucchini Cake Recipe in Different Sizes

This recipe can be made in a square 8-inch pan or a round 9-inch cake pan. If you want to use a round 8-inch pan, the bake time will be a few minutes longer. Be sure to check the center with a toothpick for doneness.

If you want to make a loaf cake using this recipe, use an 8.5×4.5-inch pan and bake for 50-60 minutes at 350°F/175°C, or until a toothpick inserted in the center of the layer comes out with a few moist crumbs.

You can also make a chocolate zucchini bundt cake with this recipe. Make 1.5 batches of batter, then heavily grease a bundt pan and fill it with batter.

Bake in a preheated 350°F/175°C oven for 45-55 minutes, or until a toothpick inserted in the center of the layer comes out with a few moist crumbs.

Can I Make This Chocolate Zucchini Cake in Advance?

You can make this cake in advance! It can sit at room temperature for up to 3 days or be stored in the fridge for up to 5 days in an airtight container.

It can also last up to a month in the freezer. Move it to the fridge the day before you plan to eat it, then let it come to room temperature before serving.

Tips for Making the Best Chocolate Zucchini Cake

• Ingredients at room temperature mix together better. Set out any cold ingredients ahead of time.
• Properly measure the flour (spoon into the cup measure, then level) or use a kitchen scale to measure your dry ingredients.
• Mix the cake batter just until the ingredients are incorporated once you add the dry ingredients. This will ensure your cake bakes up tender and soft.
• Test the center with a toothpick or scribe to check for doneness. This recipe has a lot of moisture in it, and can take a while to bake through! If the toothpick comes out gooey, it needs more time (just make sure it’s gooey batter, not a melted chocolate chip that you accidentally hit). It’s done when the toothpick comes out with a few moist crumbs or is clean.
• Even though it’s annoying, peel the zucchini before you shred it. If you don’t, the zucchini won’t fully kind of melt into the batter as it bakes, and the bits of zucchini will be much more noticeable. 

Let Me Know What You Think!

If you make this chocolate zucchini cake recipe, I’d love to hear what you think! Please leave a rating and let me know your thoughts with a comment below.

Don’t forget to tag me @chelsweets and use #chelsweets so that I can see your amazing creations on social media.

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