Instructions

• Preheat the oven to 350°F. Line a 9×13-inch baking dish with parchment paper, leaving an overhang on two sides for easy removal.
• Place 2 sticks (1 cup) salted butter and 4 ounces chopped milk chocolate in a medium, microwave-safe bowl. Microwave in 30-second intervals, stirring after each interval, until the mixture is fully melted and smooth. (Alternatively, melt over a double boiler.)
• Whisk the melted butter and chocolate with 1 1/2 cups granulated sugar, 1 tablespoon vanilla extract, and 4 large eggs until smooth and combined.
• Add 1 cup unsweetened cocoa powder, 1 cup all-purpose flour, and 1/4 teaspoon kosher salt to the chocolate mixture. Stir with a spatula until just combined and no streaks of flour remain; the batter will be thick. Do not overmix.
• Pour the batter into the prepared pan and spread into an even layer. Bake for 25–30 minutes, until the top is set and a toothpick inserted near the center comes out with a few moist crumbs (not wet batter). Remove from the oven and let the brownies cool completely in the pan (about 30–60 minutes) before proceeding.
• In a small bowl, beat 1 cup creamy peanut butter with 2 tablespoons salted butter (room temperature) until smooth and creamy.
• Drop tablespoon-sized dollops of the peanut butter mixture evenly over the cooled brownie surface. Use an offset spatula or the back of a spoon to gently spread the dollops into an even layer over the brownies. Place the pan in the freezer for 10 minutes to firm the peanut butter layer.
• While the peanut butter firms, melt 2–3 cups semi-sweet chocolate chips in a microwave-safe bowl in 30-second intervals, stirring after each interval until smooth, or melt over a double boiler. Stir well and do not overheat.
• Evenly sprinkle 1 cup Rice Krispies cereal over the peanut butter layer. Immediately pour the melted semi-sweet chocolate over the Rice Krispies, using a spatula to spread and cover the surface as needed.
• Refrigerate the pan until the chocolate is set, about 20 minutes. Use the parchment overhang to lift the slab from the pan and transfer to a cutting board.
• Cut into squares. Store the brownies in the refrigerator or in a cool, dark spot in your kitchen.