Put the sugar and butter in a large mixing bowl and whisk together until pale.
Add the eggs and vanilla and whisk, followed by the pumpkin puree.
Sift in the flour and pumpkin spice and fold together.
Spoon into the lined tins and level off.
Bake for 1 hour minutes until golden.
Leave to cool in the tin until safe to touch, then release onto a wire rack to cool completely.
Make the cream cheese frosting
Put the softened butter in a bowl and whisk until pale and creamy.
Sift in the icing sugar, add the vanilla extract and whisk until very pale, creamy and increased in volume.
Add the chilled cream cheese and fold through gently. Don't overwork it as it will loosen. If it looks like it’s starting to loosen, pop in the fridge for 10 minutes to firm up.
Assemble the cake.
Put the first cake on a board and pile about one third of the frosting on top and spread to the edges.
Place the second cake on top and pile another third of the frosting on top.
Use the remaining frosting to neatly frost the sides.
Sprinkle the crushed cookie on top.
Place the whole cake in the fridge for 1 hour to firm up before slicing and serving.