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Zucchini Brownies Recipe
Ash Tyrrell

Zucchini Brownies Recipe

I still remember the first time I stirred grated zucchini into brownie batter, half convinced I was about to ruin dessert. Instead, I pulled out the fudgiest, richest brownies I had ever baked, and nobody at the table guessed there was a vegetable hiding inside. Since then, this has become my go-to way to use up an overflowing garden harvest without anyone complaining
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Total Time 50 minutes
Ingredients Method Notes

Ingredients
  

  • Vegetable oil 1/2 cup – keeps the brownies moist without adding a strong flavor of its own
  • White sugar 1 1/2 cups – sweetens the batter and helps create that shiny, crackly top
  • Vanilla extract 2 teaspoons – rounds out the chocolate flavor, so use real vanilla if you can
  • All-purpose flour 2 cups – gives the brownies enough structure to hold together
  • Unsweetened cocoa powder 1/2 cup – go with a good-quality cocoa here since it drives most of the chocolate flavor
  • Baking soda 1 1/2 teaspoons – helps the brownies rise just enough without turning them cakey
  • Salt 1 teaspoon – balances the sweetness and makes the chocolate taste deeper
  • Shredded zucchini 2 cups – grate it fresh right before mixing so it stays moist and doesn't turn watery
  • Chopped walnuts 1/2 cup, optional – adds crunch, though you can leave these out for a smoother bite
  • Unsweetened cocoa powder 6 tablespoons
  • Margarine or butter 1/4 cup
  • Confectioners' sugar 2 cups
  • Milk 1/4 cup
  • Vanilla extract 1/2 teaspoon

Method
 

  1. Set your oven to 350°F so it's fully heated by the time your batter is ready. Grease a 9x13-inch pan with butter or cooking spray so nothing sticks later. Having this step done early keeps the rest of the process moving smoothly.
  2. In a large bowl, whisk together the vegetable oil, sugar, and vanilla extract until fully combined. This forms the base that carries most of the sweetness and moisture. Take your time here so the sugar dissolves a bit into the oil.
  3. Sprinkle in the flour, cocoa powder, baking soda, and salt directly into the wet mixture. Stir just until you no longer see streaks of flour. Overmixing at this stage can make the brownies tougher than you want.
  4. Add your freshly shredded zucchini and fold it into the batter by hand. The batter will loosen up quickly as the zucchini releases its moisture. If you're using walnuts, this is the point to stir them in too.
  5. Pour the batter into your prepared pan and spread it evenly with a spatula. Bake for about 30 to 35 minutes, checking with a toothpick near the center. You're looking for moist crumbs on the toothpick, not wet batter.
  6. Set the pan on a wire rack and let the brownies cool all the way before frosting. Frosting warm brownies will only cause it to melt and slide right off. I usually give mine at least an hour to cool fully.
  7. Whisk together the cocoa powder, melted margarine, confectioners' sugar, milk, and vanilla until smooth. Adjust with a splash more milk if it feels too thick to spread. Once the brownies are cool, spread the frosting evenly over the top.

Notes

  • I never squeeze the moisture out of my zucchini for this recipe, since that moisture is exactly what keeps the brownies fudgy
  • I grate my zucchini right before mixing instead of ahead of time, so it doesn't turn watery in the fridge
  • I like to line my pan with parchment paper so I can lift the brownies out cleanly for slicing
  • I always let the brownies cool completely before I frost them, even if I'm tempted to rush it
  • I check my brownies a few minutes early since ovens can run hot, and overbaking dries them out fast