Mud Hen Bars Recipe

1. Gather all ingredients. Preheat the oven to 350 degrees F (180 degrees C) with a rack in the bottom third position. Spray a 9×9-inch square baking pan with cooking spray, and line with parchment paper, leaving a 2-inch overhang on 2 opposite sides.

2. Whisk flour, baking powder, and salt together in a bowl until well combined. Set aside.

3. Beat butter, brown sugar, and 1/3 cup white sugar in a large bowl with an electric mixer on medium-high speed until light and fluffy, about 3 minutes.

4. Add whole egg and vanilla; beat on medium speed until well combined, about 30 seconds. With mixer running on low speed, gradually add flour mixture, beating just until combined, about 1 minute.

5. Spread mixture into an even layer on the bottom of the prepared baking pan using an offset spatula. Sprinkle semisweet chocolate chips and marshmallows on top.

6. Add egg whites to a large, clean bowl and beat with an electric mixer on medium-high speed until soft peaks form, 1 to 2 minutes. With mixer running on medium-high, add remaining 1/3 cup sugar in a slow, steady stream, beating until stiff, glossy peaks form, 1 to 2 minutes. 

7. Spoon the egg white topping over marshmallow layer and spread into an even layer using an offset spatula.

8. Bake in the preheated oven until top is golden brown and sides pull away from the edges, about 30 minutes. Cool on a wire rack until pan is cool to the touch, about 1 hour.

9. Remove from pan using parchment paper overhang; transfer to a cutting board. Cut into squares. Serve.

This recipe was developed by Jasmine Smith.