Roll loaf into a 12x16 rectangle. Spread evenly with softened butter. Then marshmallow cream. Then peanut butter. Lastly sprinkle evenly with granulated sugar.
Using a serrated knife or pizza cutter, cut dough in to even strips about 2 inches wide.
Carefully top one on top of another until they are all stacked.
Cut strips into squares. Squish each section of squares together in a loaf pan.
Cover and let rise until almost double. Bake at 350 for 30 minutes. Cover with foil the last 10 minutes if browning too quickly. Cool in pan for a few minutes, loosen edges and then transfer to cool on baking rack.