Peanut-Butter Swirl Brownies
Dollops of peanut butter filling are spooned onto brownie batter; pulling a knife back and forth through both results in a marbleized look.
- Yield: Makes 9 large or 16 small squares
Photography: Con Poulos
Source: Martha Stewart Living, February 2004
For the batter
- 8 tablespoons (1 stick) unsalted butter, cut into small pieces, plus more for pan
- 2 ounces good-quality unsweetened chocolate, coarsely chopped
- 4 ounces good-quality semisweet chocolate, coarsely chopped
- 2/3 cup all-purpose flour
- 1/2 teaspoon baking powder
- 1/4 teaspoon salt
- 3/4 cup granulated sugar
- 3 large eggs
- 2 teaspoons pure vanilla extract
For the filling
- 4 tablespoons unsalted butter, melted
- 1/2 cup confectioners' sugar
- 3/4 cup smooth peanut butter
- 1/4 teaspoon salt
- 1/2 teaspoon pure vanilla extract
Preheat oven to 325 degrees. Line a buttered 8-inch square baking pan with foil or parchment paper, allowing 2 inches to hang over sides. Butter lining (excluding overhang); set pan aside.
Make batter: Put butter and chocolates in a heatproof medium bowl set over a pan of simmering water; stir until melted. Let cool slightly.
Whisk together flour, baking powder, and salt in a separate bowl, and set aside.
Whisk granulated sugar into chocolate mixture. Add eggs, and whisk until mixture is smooth. Stir in vanilla. Add flour mixture; stir until well incorporated.
Make filling: Stir together butter, confectioners' sugar, peanut butter, salt, and vanilla in a bowl until smooth.
Pour one-third of batter into prepared pan, and spread evenly with a rubber spatula. Place dollops of filling (about 1 tablespoon each) about 1 inch apart on top of batter. Drizzle remaining batter on top, and gently spread to fill pan. Place dollops of remaining filling on top.
With a butter knife, gently swirl filling into batter, running knife lengthwise and crosswise through layers. Bake until a cake tester inserted into brownies (avoid center and edges) comes out with a few crumbs but is not wet, about 45 minutes. Let cool slightly in pan, about 15 minutes. Lift out brownies; let cool completely on a wire rack before cutting into squares.