6 ounces semisweet chocolate, coarsely chopped
1/4 cup unsweetened Dutch process cocoa
3/4 cup all-purpose flour
1/4 teaspoon baking powder
1/4 teaspoon salt
1 cup granulated sugar
2 large eggs
2 teaspoons vanilla extract
- Preheat oven to 350 degrees F. Line an 8 x 8-inch baking pan with foil and lightly spray with nonstick cooking spray.
- Melt butter, chocolate and cocoa powder in the top half of a double boiler over hot water, whisking to combine until melted and smooth. Cool slightly.
- In a separate bowl, whisk together flour, baking powder and salt; set aside.
- In the bowl of a stand mixer fitted with the whisk attachment, beat together sugar, eggs and vanilla on medium speed until pale, about 3-4 minutes. Add chocolate mixture and beat on low speed until combined. Add flour mixture and mix on low speed until just combined.
- Pour into prepared pan and smooth top. Bake until toothpick inserted near the center comes out with a few moist crumbs, not raw batter, about 35 minutes. Cool completely before cutting and serving.