Zucchini Brownies with Peanut Butter Frosting

Why You’ll Love This Recipe

I love these brownies because they’re indulgent yet slightly healthier thanks to the zucchini. The combination of chocolate and peanut butter is a classic I never get tired of, and the frosting takes them over the top. They’re a hit at family gatherings, bake sales, or whenever I want a decadent dessert that feels a little more wholesome.

Ingredients

(Here’s a tip: Check out the full list of ingredients and measurements in the recipe card below.)

For the Brownies:

• ½ cup vegetable oil (or melted butter)

• 1 cup granulated sugar

• 1 teaspoon vanilla extract

• 1 cup all-purpose flour

• ½ cup unsweetened cocoa powder

• 1 teaspoon baking soda

• ½ teaspoon salt

• 2 cups shredded zucchini (lightly packed)

For the Peanut Butter Frosting:

• ½ cup creamy peanut butter

• ¼ cup unsalted butter, softened

• 1 teaspoon vanilla extract

• 1 cup powdered sugar

• 2–3 tablespoons milk (to thin as needed)

Directions

1. Preheat oven: I set my oven to 350°F (175°C) and grease or line a 9×13-inch baking dish.

2. Make the brownie batter: In a mixing bowl, I whisk together the oil, sugar, and vanilla. I stir in the flour, cocoa powder, baking soda, and salt until just combined. Then I fold in the shredded zucchini. The batter looks thick at first, but the zucchini releases moisture as it bakes.

3. Bake: I spread the batter evenly in the pan and bake for 25–30 minutes, until a toothpick comes out with just a few moist crumbs. I let the brownies cool completely before frosting.

4. Prepare the frosting: In a separate bowl, I beat together the peanut butter, butter, and vanilla until creamy. I add the powdered sugar and milk, a little at a time, until smooth and spreadable.

5. Frost and serve: Once cooled, I spread the frosting evenly over the brownies, slice into squares, and serve.

Servings and timing

This recipe makes about 16 brownies and takes around 45 minutes total (15 minutes prep, 30 minutes bake, plus cooling time for frosting).

Variations

• Double chocolate: I stir chocolate chips into the brownie batter for extra fudginess.

• Nut-free option: I swap the frosting for a chocolate buttercream or cream cheese frosting.

• Healthier twist: I use coconut sugar instead of granulated sugar and whole wheat pastry flour instead of all-purpose.

• Frosting alternative: I sometimes top with a drizzle of melted chocolate instead of full frosting for a lighter finish.

• Add crunch: A sprinkle of chopped peanuts or walnuts on top gives extra texture.

Storage/Reheating

I store these brownies in an airtight container at room temperature for up to 3 days or in the fridge for up to 5 days. For longer storage, I freeze them (frosted or unfrosted) for up to 2 months, layering with parchment paper to prevent sticking.

FAQs

Do I need to squeeze the zucchini?

I don’t usually — the extra moisture helps keep the brownies fudgy. If my zucchini is very watery, I blot it lightly with a paper towel.

Can I make these gluten-free?

Yes, I swap in a 1:1 gluten-free baking flour blend.

Can I use natural peanut butter for the frosting?

Yes, but I make sure it’s stirred well since natural peanut butter can separate. The texture may be a little softer.

Can I skip the frosting?

Definitely. The brownies are delicious on their own, but the peanut butter frosting really makes them special.

How do I know when the brownies are done?

I check with a toothpick — if it comes out with a few moist crumbs (not wet batter), they’re ready.

Conclusion

These Zucchini Brownies with Peanut Butter Frosting are rich, fudgy, and impossible to resist. I love how the zucchini keeps them moist while the peanut butter frosting adds a decadent finish. Whether I’m sneaking in veggies for the family or just craving chocolate, this recipe is always a winner.