Found this recipe in Maw Maw's Old Church Cookbook and have enjoyed making it ever since. A very simple but good recipe. They are not like the mud bar that has chocolate on top. Has the taste and texture of what grandma use to make.
Preheat oven to 350 degrees. Beat together the granulated sugar and butter until creamy. Beat in 1 whole egg and 2 egg yolks (put aside the whites for later). In a separate bowl, mix together the flour, salt and baking powder. Add to the butter mixture and mix well. Spread into 9x13" pan. Bake the crust for 5 minutes before adding marshmallows. Let cool and then sprinkle with marshmallows, nuts and chocolate chips.
Beat egg whites until stiff peaks form. Fold in the brown sugar.
Spread the meringue mixture and brown sugar mixture over the marshmallows and chocolate chips.
Bake in a preheated 350 degree oven for about 30 minutes or until bars are a deep golden brown and the crust is cooked through. If the meringues starts to brown to quickly cover lightly with a piece of foil sprayed with baking spray.