Instructions

  1. Set oven to 350 degrees F.
  2. Grease a 15 x 10-inch jelly-roll pan.
  3. For the cake; in a large bowl beat the melted butter with the next 5 ingredients until combined and smooth.
  4. Add in flour; mix until blended.
  5. Pour the batter into prepared baking pan.
  6. Sprinkle the nuts over the top then push down slightly into the batter.
  7. Bake for about 20 to 22 minutes or until the cake tests done.
  8. At this point prepare the chocolate frosting while the cake is baking (the cake must be warm before adding on).
  9. For the frosting; in a medium bowl beat all ingredients together until smooth and blended; set aside to pour over warm cake.
  10. Remove from oven then sprinkle the mashmallows on top; return to oven for another 5 minutes.
  11. Drizzle the prepared chocolate frosting over top of the marshmallows.