Peanut Butter Swirl Brownies | America's Test Kitchen

Ingredients

• 3 ounces (85 grams) unsweetened chocolate, chopped
• 8 tablespoons unsalted butter (1 stick), cut into chunks
• 1 cup (7 ounces/198 grams) sugar
• 1/2 teaspoon baking powder
• 1/4 teaspoon table salt
• 2 large eggs
• 1 teaspoon vanilla extract
• 2/3 cup (3⅓ ounces/94 grams) all-purpose flour
• 1/3 cup peanut butter, at room temperature
• 4 ounces (113 grams) semisweet or bittersweet chocolate, chopped
• 1 tablespoon vegetable oil