The Scream (pumpkin and marshmallow bake)

Please do not snigger at my attempt at being arty. I hope The Scream is recognisable enough.
To cook this sweet concoction you will need
1 tin of Libby's solid pack pumpkin (or indeed your own mashed pumpkin if you have plenty after carving the pumpkin for the Hallowe'en. I cooked a soup with ours, and our pumpkin wasn't big to start with, so the Libby's it was), 425g
1 small tin of evaporated milk, 170g
125 g self-raising flour
30 g melted butter
130 g demerara sugar
1 medium egg
1 tsp ground cinnamon
1 tsp vanilla extract
half a tsp of ground nutmeg or less
large marshmallows
Dr Oetker ready to roll icing and writing icing for decoration, also leave one marshmallow for the head

In a large mixing bowl mix together all the ingredients: the pumpkin, evaporated milk, butter, sugar, egg and spices. Pour into a big greased tray or ceramic dish(size 19x29cm) and bake at 180C for about half an hour, until the pumpkin bake is firm to the touch. Add the marshmallows around the edges and put the dish back in the oven for them to melt into a gooey mess.
Take out of the oven, let it cool down, decorate with the writing icing, doing spider webs. Using the remaining marshmallow and writing icing, make a head for your figure. I inserted half a bamboo skewer inside the figure as it kept falling. The figure itself is made from Ready to roll icing, which comes in 5 colours (I used the black and yellow here).
Cut into slices like brownies before serving. Have fun decorating!