The Evolution of the Dark Chocolate Zucchini Brownie

I've been in search of a good dark chocolate brownie recipe and at the same time, I've been searching for more ways to use up all the summer squash that comes this time of year. So, when I found a well reviewed zucchini brownie recipe, I thought I'd had it made. But I didn't care for the original recipe so I experimented a bit. My favorite version is at the bottom of this post.

The recipe I started out with can be found here.
Ingredients:

• 1/2 cup vegetable oil
• 1 1/2 cups white sugar
• 2 teaspoons vanilla extract
• 2 cups all-purpose flour
• 1/2 cup unsweetened cocoa powder
• 1 1/2 teaspoons baking soda
• 1 teaspoon salt
• 2 cups shredded zucchini
• 1/2 cup chopped walnuts

• 6 tablespoons unsweetened cocoa powder
• 1/4 cup margarine
• 2 cups confectioners' sugar
• 1/4 cup milk
• 1/2 teaspoon vanilla extract

Directions:
1. Preheat oven to 350 degrees F (175 degrees C). Grease and flour a 9x13 inch baking pan.
2. In a large bowl, mix together the oil, sugar and 2 teaspoons vanilla until well blended. Combine the flour, 1/2 cup cocoa, baking soda and salt; stir into the sugar mixture. Fold in the zucchini and walnuts. Spread evenly into the prepared pan.
3. Bake for 25 to 30 minutes in the preheated oven, until brownies spring back when gently touched. To make the frosting, melt together the 6 tablespoons of cocoa and margarine; set aside to cool. In a medium bowl, blend together the confectioners' sugar, milk and 1/2 teaspoon vanilla. Stir in the cocoa mixture. Spread over cooled brownies before cutting into squares.

I made this recipe the first time without any changes except skipping the icing. Also, I used the Special Dark cocoa powder. I found the brownies to be very good but quite cakey so I set about modifying the recipe for a more fudgey brownie. I researched what makes brownies more cakey versus more fudgey and found that reducing egg, flour and baking soda should do it. So, I went about it the scientific way and changed one thing at a time. First I reduced the baking soda to 1/2 teaspoon. This definitely made the brownies less cakey, but they were still pretty cakey IMO. Next, I reduced the flour to 1 1/2 cups. They helped a LOT towards making the brownies more fudgey. Still not as fudgey as some I've had in the past. Next, I reduced the baking soda to just a scant 1/4 teaspoon. Next, I added more cocoa powder, bringing the amount up to 3/4 cup. Now these brownies are pretty fudgey! So, the ingredients for my current recipe is:

• 1/2 cup vegetable oil
• 1 1/2 cups white sugar
• 2 teaspoons vanilla extract
• 1 1/2 cups all-purpose flour
• 3/4 cup unsweetened cocoa powder
• 1/4 teaspoons baking soda
• 1 teaspoon salt
• 2 cups shredded zucchini
• 1/2 cup chopped walnuts (optional)

Finally, I jazzed them up a bit by adding a cream cheese swirl. Wow! These are currently my favorite brownies! For the cream cheese swirl:
Cream Cheese Layer:

• 8 ounces (227 grams) full fat cream cheese, at room temperature
• 1/4 cup (65 grams) granulated white sugar
• 1/2 teaspoon pure vanilla extract
• 1 large egg

Beat all the ingredients for the brownies together, minus the ingredients for the cream cheese swirl. After putting the brownie batter in the pan, beat the ingredients for the cream cheese swirl together until smooth and spoon the cream cheese mixture on top of the brownie mixture. Draw a knife through it repeatedly to swirl it. Then bake as usual.