1/2 cup butter
3/4 cup all-purpose flour
1/2 teaspoon baking powder
1/2 teaspoon kosher salt
1/2 cup unsweetened cocoa powder (preferably dark)
3/4 cup plus 2 tablespoons granulated sugar, divided
1/2 cup dark brown sugar
1/2 cup dark chocolate chunks
3 ounces plus 2 ounces champagne, divided
Confectioners’ sugar for dusting
2 pints raspberries
Whipped cream, if desired
Preheat your oven to 350° F. Lightly grease the bottom of an 8×8-inch square baking pan with butter or shortening and set aside.
In a medium bowl, combine 2 ounces of champagne, raspberries, and 2 tablespoons of sugar. Mash slightly with the back of a spoon to lightly crush the berries and combine. Cover bowl and refrigerate for 2 hours.
Melt (just barely) the butter in a medium-sized, microwave-safe bowl. You don’t want the butter so hot that it’s boiling or steaming. Depending on the power of your microwave, I recommend melting the butter in 10- to 15-second segments on high power. Remember, the butter will continue to melt after the microwave is done.
Add first your 3 ounces of remaining champagne and then the eggs to the melted butter. Stir in flour, baking powder, salt, cocoa powder, granulated sugar and brown sugar. Mix just until blended, then fold in the dark chocolate chunks. Spread the champagne brownies batter in your prepared baking pan.
Bake for about 30 minutes, or until the brownies are dry around edges. A toothpick inserted in the center should come out almost clean and slightly moist. Cool the brownies completely before cutting, about 1 hour.
Lightly dust the champagne brownies with confectioners’ sugar and cut into 4 rows by 4 rows to make 16 brownies. Spoon champagne-macerated raspberries onto each serving with whipped cream, if desired.