These Chocolate Peanut Butter Zucchini Muffins are based on my classic Chocolate Zucchini Muffins, with the bonus of peanut butter. They’re rich, moist, and packed with chocolatey flavor. You’d never guess they’re loaded with shredded zucchini, which keeps them incredibly soft! Perfect for using up extra zucchini, these muffins make a delicious breakfast, snack, or easy dessert. If you love zucchini, check out my ultimate list of zucchini recipes for even more ways to use it!

Chocolate Peanut Butter Zucchini Muffins on a white table with fresh zucchini and peanut butter chips nearby.

Ingredients & Substitutions

Vegetable Oil: This recipe uses vegetable oil to keep the muffins extra moist and tender. You can substitute it with canola oil, melted coconut oil, or even light olive oil if you prefer. Just avoid strongly flavored oils, which can affect the taste.
Cocoa Powder: I use Dutch-processed cocoa powder for a deeper, richer chocolate flavor. If you only have regular unsweetened cocoa powder on hand, it’ll still work, but the flavor will be a little lighter and more classic chocolate cake-like.
Zucchini: No need to drain the zucchini, just finely shred it and toss it right in! The natural moisture from the zucchini is what makes these muffins so soft and tender. If your zucchini seems extra watery, you can lightly blot it, but don’t squeeze it dry.
Chocolate Chunks: I like using semi-sweet chocolate chunks because they melt into gooey pockets of chocolate in every bite. Chocolate chips work just as well if that’s what you have, or try dark chocolate chunks for a richer flavor. Even a chopped-up chocolate bar works great here! I also save a few for the topping (before baking), but that is optional.
Peanut Butter Chips: I love the combination of chocolate and peanut butter, so it just made sense to add peanut butter chips to these chocolate muffins! If you love the combination as much as I do, check out my Chocolate Peanut Butter Ooey Gooey Cake, too!

Chocolate Peanut Butter Zucchini Muffin with its wrapper pulled down on a cutting board surrounded by more muffins and fresh zucchini.

Using Shredded Zucchini In Chocolate Muffins: Tips and Tricks

I’ve made countless recipes with zucchini, so I’ve learned a few things about how to get the best results when adding shredded zucchini to baked goods like these chocolate muffins. Here’s what works every time:

Use finely shredded zucchini to make sure it blends well and spreads evenly through the batter. I usually use a box grater or food processor for this.
No draining needed (at least, not for this recipe)! The natural moisture from the zucchini is what keeps muffins soft and tender. If your zucchini feels really watery, a gentle blot with a paper towel is fine, but don’t squeeze it dry, or you’ll lose that great texture. Always check recipes carefully; sometimes, the zucchini should be drained (like in my Chocolate Zucchini Cookies).
Measure after shredding. Zucchini sizes and moisture can vary a lot, so I always shred first and then measure. For this recipe, about 3 cups (which is roughly 2 to 3 medium zucchini) is just right.
Fold it in last and gently. Overmixing can make muffins tough, so I always add the zucchini at the end and fold it in carefully.

Using zucchini is one of my favorite ways to sneak vegetables into a sweet treat! And, I promise, no one will taste a thing, except a deliciously moist chocolate muffin!

Pan of Chocolate Peanut Butter Zucchini Muffins on a white table with chocolate, peanut butter chips, and zucchini nearby.

Chocolate Chunks vs Chocolate Chips: Which Is Best for Muffins?

When it comes to baking muffins, choosing between chocolate chunks and chocolate chips can make a subtle but delicious difference.

Chocolate chunks are larger and melt into gooey pockets of chocolate, creating rich, melty bites throughout your muffin. They also give a more rustic, homemade look with uneven chocolate pieces.

Chocolate chips, on the other hand, hold their shape better during baking, giving you little bursts of chocolate in every bite. They’re great if you want a consistent chocolate texture and look.

For these muffins, I prefer chocolate chunks because they melt into gooey pockets of chocolate. But chocolate chips work just as well and still add plenty of flavor. Try both to see which texture you like best!

Why You’ll Love Chocolate Peanut Butter Zucchini Muffins

These muffins are the perfect combination of rich chocolate and creamy peanut butter flavors, making each bite irresistibly delicious. Thanks to the shredded zucchini, they stay wonderfully moist and tender without tasting like vegetables at all! They’re a sneaky way to add some extra nutrition to your day, perfect for breakfast, snacks, or even a quick dessert. Plus, they’re easy to make and freeze well, so you can enjoy them anytime.

Can I Make Chocolate Peanut Butter Zucchini Muffins into a Loaf?

Yes! You can easily turn this chocolate peanut butter zucchini muffin batter into a loaf. Use a standard 9×5-inch loaf pan, greased or lined with parchment paper. Bake at 350°F, but expect the baking time to increase to about 50–60 minutes. Check for doneness by inserting a toothpick; when it comes out mostly clean, your zucchini bread loaf is ready. The loaf will be denser than the muffins, but just as moist and packed with rich chocolate and peanut butter flavor. This easy chocolate zucchini bread is perfect for slicing and sharing or enjoying as a quick breakfast or snack.

Halved Chocolate Peanut Butter Zucchini Muffin on a white table with other muffins nearby.

How to Store Chocolate Peanut Butter Zucchini Muffins

To keep your Chocolate Peanut Butter Zucchini Muffins fresh, let them cool completely before storing. Place them in an airtight container at room temperature, where they’ll stay moist and delicious for 2 to 3 days. If your kitchen is warm or humid, storing muffins in the refrigerator can help extend freshness by a few more days, but note this might make them a little drier. For best results, enjoy them within a few days of baking.

Can I Freeze Chocolate Peanut Butter Zucchini Muffins?

Yes! Chocolate Peanut Butter Zucchini Muffins freeze really well, making them perfect for meal prep or keeping on hand. After the muffins have cooled completely, wrap each one individually in plastic wrap or aluminum foil, then place them in a freezer-safe bag or container. Freeze for up to 3 months. When you want to eat one, thaw at room temperature or warm in the microwave for 15-20 seconds to bring back that soft, gooey texture.

What the Test Kitchen had to say about this recipe:

Autumn

Zucchini adds so much moisture to these muffins! Plus, they are so chocolatey!

Elizabeth

I love chocolate with peanut butter, and I can't believe how moist these muffins are. Wow. My only suggestion would be to add a few more peanut butter chips.