Dessert: Triple Chocolate Brownies

I got this recipe from my mom, who says she got it from Cooks Illustrated (the recipe appears to be here; I can't read it because I'm not a subscriber).  It's my current favorite brownie recipe, and I've made it many times already!  I thought it seemed a bit complicated when I first read it, but once I actually tried it, I found it was quick and simple in practice.

Chewy Fudgy Triple Chocolate Brownies

5 ounces semi-sweet chocolate, chopped
2 ounces unsweetened chocolate, chopped
3 tablespoons cocoa powder
8 tablespoons unsalted butter, cut into quarters
3 large eggs
1 1/4 cups sugar
1 cup all-purpose flour
2 teaspoons vanilla extract
1/2 teaspoon salt

Preheat oven to 350 degrees Fahrenheit.  Spray an 8-inch square baking pan with non-stick vegetable spray.  Fold two 12-inch pieces of foil lengthwise so they measure 7 inches wide.  Fit one sheet in bottom of greased pan, pushing it into corners and up the sides of the pan; overhang with help in removal of baked brownies.  Fit second sheet in pan in the same manner, perpendicular to the first.  Spray foil with non-stick cooking spray.

In a medium heat-proof bowl set over a pan of almost-simmering water, melt chocolates and butter, stirring occasionally, until mixture is smooth.  Whisk in cocoa until smooth.  Set aside to cool slightly.
Whisk together eggs, sugar, vanilla, and salt in a medium bowl until combined, about 15 seconds.  Whisk warm chocolate mixture into egg mixture; then stir in flour with a wooden spoon until just combined.  Pour mixture into prepared pan, spread into corners, and level surface with a rubber spatula.

Bake until slightly puffed and toothpick inserted into center comes out with a small amount of sticky crumbs clinging to it, 35-40 minutes.  Cool on wire rack to room temperature, about 2 hours, then remove brownies from pan using foil handles.  Cut into one-inch squares (do not cut until ready to serve).

I never really saw the point of all the tin-foil, so after obediently doing it that way a few times, I have since done without the foil, simply spraying the dish, and have been happier without the foil.

I have also toyed around with using whole-wheat flour, whether half all-purpose and half regular whole-wheat, or, most recently, replacing all of the all-purpose flour with whole-wheat pastry flour.  I thought both worked out fine.

I have debated trying to replace some (not all) of the butter with a healthier substitute, whether applesauce or just a different kind of oil, but I'm not sure it would work out and haven't had the courage to try. (Don't want to waste all that delicious chocolatey goodness!)  If you have any suggestions or advice, I'd love to hear it.