a huge zucchini brownie being held up with a big bite taken out

Zucchini Brownies

Hands down the best Zucchini Brownies recipe because they're very fudgy, easy to make, and slathered with peanut butter frosting and chocolate glaze. 
Course Dessert, gluten free dessert
Cuisine American
Prep Time 15 minutes
Cook Time 20 minutes
Total Time 35 minutes
Servings 32
Calories 218kcal
Author Melissa Erdelac


Zucchini Brownies:

  • 16 ounces zucchini, cut into chunks (about 4 cups)
  • 6 tablespoons butter, melted
  • 6 eggs
  • 2 teaspoons vanilla extract
  • 1 1/2 cup sugar
  • 2/3 cup cocoa powder, preferably Dutch processed
  • 1/2 teaspoon baking powder
  • 1/2 teaspoon salt
  • 1 cup all-purpose flour or all-purpose gluten free flour
  • 1 cup chocolate chips

Peanut Butter Frosting:

  • 3/4 cup creamy peanut butter
  • 1/2 cup unsalted butter, softened
  • 1 1/4 cups powdered sugar
  • 1 teaspoon vanilla extract
  • 1/2 teaspoon salt
  • 1 tablespoon milk

Chocolate Glaze:

  • 3/4 cup chocolate chips
  • 3 tablespoons milk


Zucchini Brownies:

  • Preheat oven to 350ºF. Grease a 9X13" pan and set aside.
  • In a food processor place zucchini chunks, melted butter, eggs, and vanilla. Process until smooth. If you are making brownies without a food processor or in a blender, see RECIPE NOTES.
  • Add sugar, cocoa powder, baking powder, salt, and flour. Process until just combined. Add chocolate chips and pulse a few times to break chips up just a bit.
  • Pour into prepared 9X13" pan and bake for 40-44 minutes, or until toothpick inserted in middle comes out without wet batter. Cool completely in pan while making peanut butter frosting.

Peanut Butter Frosting:

  • In a medium mixing bowl, use a hand mixer to beat together on LOW SPEED peanut butter, softened butter, powdered sugar, vanilla, and salt. Once all the ingredients are incorporated, scrape down bowl. Increase speed to HIGH and beat until smooth and fluffy, about 1 minute.
  • Add 1 tablespoon of milk and mix well. If frosting is too thick, add a splash more of milk until you reach desired consistency. Spread peanut butter frosting on cooled brownies.

Chocolate Glaze:

  • In a microwave safe bowl place chocolate chips and milk. Melt in microwave for 30 seconds. Chips will not be fully melted, but stir until smooth.
  • Pour glaze over peanut butter frosting and spread with an offset spatula. Chill brownies for 15-30 minutes to set chocolate glaze before cutting into bars. 



    Tips and Tricks for Making Zucchini Brownies
    • Don't have a food processor? No problem. Use a grater and measure out 3 cups of shredded zucchini instead.
    • If you don't have a kitchen scale, cut enough cubed zucchini to fill 4 cups.
    • This recipe can easily be halved and baked in a 8" or 9" square pan. Bake for 25-30 minutes.
    • Dutch processed cocoa powder is preferred for this recipe, but natural unsweetened baking cocoa can be substituted. Read more about when Dutch processed cocoa powder is preferred on my Fudgy Flourless Chocolate Cookies post.
    • Zucchini Brownies can also be made in a blender or Vitamix, but you may want to stick to a half recipe to make sure all the ingredients fit. 
    Recipe adapted from King Arthur Flour and The Stay at Home Chef


    Calories: 218kcal | Carbohydrates: 26g | Protein: 4g | Fat: 11g | Saturated Fat: 5g | Cholesterol: 45mg | Sodium: 165mg | Potassium: 127mg | Fiber: 1g | Sugar: 21g | Vitamin A: 250IU | Vitamin C: 2.6mg | Calcium: 30mg | Iron: 0.9mg