Preheat the oven to 350° levels
In a big bowl, whisk collectively the melted butter and the subsequent 5 elements.
Stir in flour and chopped pecans.
Unfold the dough (it will likely be thick) in a greased and floured 15 x 10-inch jelly pan (or use a deep dish cookie sheet).
Bake at 350° for 20 to 25 minutes or till a picket decide inserted within the middle comes out clear. Be aware: Cut back the temperature by 25 levels if utilizing a darkish baking pan.
Take away from oven; cowl scorching cake evenly with marshmallows.
Return to oven and bake for five minutes.
Put together the chocolate frosting: Beat all elements along with an electrical mixer till clean.
Pour the chocolate icing over the new cake.
Let the cake cool utterly earlier than reducing into squares!