Rich, fudgy double chocolate zucchini bread with a secret ingredient, sour cream! With chocolate chips throughout, it tastes more like cake than veggies.

close up overhead photo of Double Chocolate Zucchini Bread

Why this recipe works

If you really want to know the secret to moist double chocolate zucchini bread, it’s the addition of sour cream. It’s like a decadent slice of chocolate cake dotted with pockets of melty chocolate. Oh, and we can’t forget the hidden veggies packed inside. You can hardly even tell they are there! This recipe, hands down, makes the best chocolate zucchini bread I’ve ever sunk my teeth into. Better yet, it makes two loaves. One for now, and one for later (or to share).

It’s zucchini season, baby. That means lots and lots of zucchini recipes on the horizon to use up that bountiful harvest. A rich double chocolate zucchini bread overflowing with chocolate chips is high on my annual list to make for family and friends. I’ll, of course, be making my easy cake mix zucchini muffins as well for those who aren’t chocolate fanatics among many, many of my other favorite ways to use zucchini in both savory and sweet dishes.

slices of Double Chocolate Zucchini Bread stacked on a plate

Ingredients you will need

Get all measurements, ingredients, and instructions in the printable version at the end of this post.

ingredient to make Double Chocolate Zucchini Bread

Ingredient Info and Substitution Suggestions

ZUCCHINI – You will need about 2 large zucchinis or 3 medium zucchinis to yield 3 cups grated. You don’t want your grated zucchini overly wet, nor do you want it dry. Give it a gentle pat with a paper towel or tea towel before incorporating if it needs it.

FLOUR – It’s truly best to use a kitchen scale to weigh out your flour. If you do not own a scale, use the spoon and sweep method when measuring. Scoop spoonfuls of flour into a measuring cup until overflowing. Then, use the back end of a butter knife to gently sweep off the excess. Do not pack the flour into the cup, this is how you overmeasure and end up with dense, dry quick bread.

COCOA POWDER – I would recommend sticking to natural unsweetened cocoa powder here. The unsweetened cocoa powder works hand in hand with the baking soda to give it a good rise. You can substitute with Dutch processed cocoa powder, but the loaf won’t rise as much.

CHOCOLATE – We use mini chocolate chips in our zucchini bread. Why? Because they distribute evenly throughout the batter and don’t sink to the bottom as much as regular chocolate chips tend to. You can absolutely substitute with regular chocolate chips or even chop up a bar of baking chocolate instead if that’s what you have on hand.

SOUR CREAM – This is the key ingredient for moist chocolate zucchini bread. The fat in sour cream gives the bread a softer, more supple crumb and adds richness. If needed, you can substitute with Greek yogurt.

ORANGE ZEST – It might look interesting to have orange zest in a chocolate quick bread recipe, but it helps enhance the chocolatey flavor. You won’t be able to taste it!

How do you keep chocolate chips from sinking in the batter?

There’s a couple ways to avoid chocolate chips from sinking in your zucchini bread batter.

First, use mini chocolate chips. Mini chips are lighter, therefore, do not sink nearly as much as regular chips. I’ve found that they distribute more evenly throughout so you get bits of chocolate in every bite.

Secondly, toss the chocolate chips in a spoonful of the flour mixture before mixing them in. This gives the chips somewhat of a “grip” in the batter so they don’t immediately sink.

How to Make Double Chocolate Zucchini Bread

These step by step photos and instructions are here to help you visualize how to make this recipe. You can Jump to Recipe to get the printable version of this recipe, complete with measurements and instructions at the bottom.

Preheat oven to 350 degrees. Butter and flour two 8 inch loaf pans and set aside. I actually used one 8″ disposable pan to give away and a larger 9″ one for me and the batter divided perfectly. So you should get 2 very full 8″ pans or slightly less full 9″.
Mix topping ingredients in a small bowl and set aside.
Place flour, cinnamon, baking soda, salt, and cocoa powder in a small bowl and whisk to combine. Set aside.
With a stand or hand mixer beat oil, white sugar, brown sugar, and eggs until combined and slightly fluffy, 1-2 minutes.
Add vanilla and sour cream and mix until combined.
Gently stir in the grated zucchini (and zest if you’re using).
Take a spoonful of the flour mixture and stir in with the chocolate chips (that will help keep them evenly distributed) If you only have regular chocolate chips, or a chocolate bar, just give it a chop so it’s the size of mini chocolate chips.
Add the remaining flour mixture to the batter and stir just until combined. Add chocolate chips and stir to combine.
Divide the batter between the two pans and sprinkle the chocolate chips and sugar topping over each. Place pans on a cookie sheet for easy moving.
Bake in your preheated 350 degree oven for 50-60 minutes.
When it’s done, a toothpick or skewer should come out without goopy batter on it and the top will be gorgeous and cracked with sugar.
Let it cool on a rack for 5-10 minutes and then remove from pans.

Frequently Asked Questions & Expert Tips

Should you remove excess water from zucchini when making zucchini bread?

Yes, but you don’t want to remove too much, as that’s what helps keep it tender and moist. Your best bet is to place the shredded zucchini on a paper towel or tea towel and gently blot off any excess water. You can very gently squeeze the shredded zucchini if needed, but you certainly don’t want it dry!

Should you peel zucchini before grating it?

There’s no need to peel zucchini before grating it, especially for zucchini bread. You won’t be able to tell the skin has been left on as it softens when baked. Wash your zucchini before grating, and you’re good to go!

Can I use frozen zucchini?

Sure! Though you’ll want to thaw it before beginning. Frozen zucchini has tons of moisture, which you don’t want too much of in your batter. Too much moisture can cause dense, gummy bread.

How do you store chocolate zucchini bread?

Allow your zucchini bread to fully cool, then wrap it well with plastic wrap and place inside a sealed zipper bag or airtight container. Keep at room temperature for up to 4 days or transfer to the fridge for up to 1 week.

Can you freeze chocolate zucchini bread?

Absolutely! I have frozen many of these loaves over the years. Wrap the fully cooled bread in plastic wrap followed by a layer of aluminum foil. Freeze for 2-3 months.

Double Chocolate Zucchini Bread sliced on parchment paper

Serving Suggestions

Incidentally, double chocolate zucchini bread tastes more like cake than a quick bread, so it really could be enjoyed as dessert! Serve it alongside coffee in the morning, as dessert, or a little treat to snack on throughout the day.

Since this recipe makes two loaves, I would recommend either freezing the other loaf or packaging it up for friends, family, or neighbors. Hope you love it as much as I do!

More Zucchini Recipes

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This recipe was slightly adapted from Our Best Bites Chocolate Zucchini Bread. This post was originally published on this blog on Oct. 23, 2009.