Zucchini Brownies

These are some of my favorite brownies, they're fudge and velvety and taste sooooo amazing when chilled.  Adapted from Mel's Kitchen Cafe.

INGREDIENTS

•  3/4 cup (6 ounces, 12 tablespoons) butter
•  6 ounces (1 cup) chopped semisweet chocolate or good-quality chocolate chips that melt well 
•  1/4 cup (1 ounce) natural unsweetened cocoa powder
•  1/2 cup (3.75 ounces) packed light brown sugar
•  1 cup (7.5 ounces) granulated sugar
•  1 teaspoon vanilla extract
•  1 large egg yolk or 1 whole egg
•  1 teaspoon baking soda
•  3/4 teaspoon salt
•  2 cups lightly packed finely shredded zucchini that has been wrung dry (see note)
•  1 1/4 cups (6.25 ounces) all-purpose flour
•  1 1/2 cups (8 ounces) chocolate chips (we like to use regular and mini)--1 cup for batter, 1/2 cup for the top

INSTRUCTIONS
Preheat the oven to 350 degrees F. Lightly coat a 9x13-inch aluminum pan (see note) with nonstick cooking spray or line with foil and coat with cooking spray (for easier cleanup and to lift out the brownies in one slab after baking, if desired).

In a microwave-safe bowl (you can also do this in a pan on the stovetop), add the butter, chocolate chips, and cocoa. Cook for one minute increments, stirring in between, until the mixture is melted and smooth (don't overheat).

Add the brown sugar and white sugar; mix well. Add the vanilla and egg yolk and mix again until well-combined.Stir in the baking soda and salt until well-combined.

Add the zucchini and stir until evenly mixed. Add the flour and ONE CUP of the chocolate chips (or chunks) and stir until just combined (don't overmix).

Spread the batter evenly in the prepared pan. Sprinkle the remaining cup of chocolate chips over the top.

Bake for 25-30 minutes until the edges are set and the middle is soft (a toothpick inserted in the center will come out clean or with a few moist crumbs - but if there is wet batter on the toothpick, bake for a few more minutes). Don't overbake or the brownies can be dry. Let the brownies cool in the pan before cutting. These taste amazing chilled.  And freeze well!

NOTES
Cut the zucchini with the shredding disk on the food processor.  Then to dry the zucchini, place zucchini in a tea towel.  Wrap up and twist the ends like a peppermint or tootsie roll candy.  Then squeeze tightly with a twisting motion over the sink and let the excess liquid drip out.   You do want it as dry as possible (a key to not ending up with zucchini CAKE instead of zucchini BROWNIES).  1 small zucchini yields about 1 cup.  A medium zucchini can yield 2-3 cups.