Peanut Butter Rice Krispies Brownies

Step 1
Preheat oven to 350 degrees F (175 degrees C). Grease a 9×13-inch baking dish.

Step 2
Beat brownie mix, vegetable oil, water, and 2 eggs in a bowl until batter is smooth.

Step 3
Whisk flour, baking powder, and salt together in a small bowl.

Step 4
Beat peanut butter, brown sugar, and 2 tablespoons butter together in another bowl with an electric mixer until light and creamy. Beat 1 egg and vanilla into peanut butter mixture until fluffy. Stir flour mixture into peanut butter mixture until just blended.

Step 5
Pour brownie batter in the prepared baking dish. Drop peanut butter mixture by small spoonfuls over the brownie batter.

Step 6
Bake brownies in the preheated oven until a toothpick inserted in the center of the brownies comes out clean, about 30 minutes; cool.

Step 7
Melt 1/4 cup butter in a large saucepan over medium heat; add marshmallows and stir until marshmallows are melted. Cook mixture until butter and marshmallow flavors are combined, about 2 minutes; remove from heat.

Step 8
Spread 1/3 the marshmallow mixture over the cooled brownies. Stir crispy rice cereal into remaining 2/3 the marshmallow mixture; press in an even layer on top of the brownies. Refrigerate until set, about 15 minutes; cut into squares.