Mud Hen Bars

1/2 cup butter, at room temperature
1 cup granulated sugar
3 large eggs, divided (1 egg, 2 yolks, and 2 egg whites)
1 teaspoon vanilla extract (I added this)
1 1/2 cups all-purpose flour
1 teaspoon baking powder
1/4 teaspoon salt
1/2 cup semi-sweet chocolate chips
1 cup mini marshmallows
1 cup chopped nuts (I left these out)
1 cup light brown sugar

1. Preheat oven to 350 degrees F. Grease a 9x13 pan and set aside.

2. In the bowl of a stand mixer, beat together butter and granulated sugar until creamy. Beat in 1 whole egg and 2 egg yolks (put aside the whites for later.) Beat in the vanilla extract.

3. In a separate medium bowl, whisk together the flour, salt, and baking powder. Add the dry ingredients to the wet ingredients. Blend until just combined. Spread mixture into 9x13" pan. Sprinkle with marshmallows, chocolate chips, and nuts-if using.

4. Beat egg whites until stiff peaks form. Gently fold in the brown sugar. Spread mixture evenly over marshmallows and chocolate chips. Bake for about 30 minutes or until bars are a deep golden brown. Let bars cool completely. Cut into squares and serve.