Pre-heat your oven to 160C Fan/350F/Gas Mark 4, grease and line a 12" x 9" traybake tin
To make the sponge, mix together the oil and light brown sugar until smooth
Then whisk in the eggs and pumpkin puree
Then whisk in the self raising flour, cinnamon, mixed spice, ginger and nutmeg
Pour the mixture into the tin, smooth it out into an even layer, and bake for 25-30 minutes or until a skewer inserted in the centre comes out clean. Leave to cool fully
To make the cream cheese frosting use an electric hand whisk to mix together the butter and icing sugar, when they start to come together, add the cream cheese and vanilla extract and mix until smooth
To make the cinnamon sugar, mix the ingredients together
Spread the frosting on top of the sponge, then add fondant pumpkins and the cinnamon sugar, or other decoration of your choice
To serve, slice into squares. Store any leftovers in the fridge and eat within 3 days