Place 1 x 75ml of butter, water and salt into a medium sized pan and heat until the butter starts to melt. Remove from the heat and continue stirring until the butter is fully melted.
Add the flour and Pumpkin Spice in one batch and stir like mad (Ths is the magic bit where the mix starts to looks like a dough).
Place back on the hear and keep stirring for 2-3 minutes. The dough should start to have a shiny sheen.
Remove the dough and leave to cool completely (at least 8-10 minutes). I place it into a metal bowl to help cool quickly.
While the dough is coooling, preheat the oven to 200C and line a baking tray with baking parchment.
Whisk the eggs and add to the dough mixture. Mix together using an electric mixer for at least 4-5 minutes. The dough should still be thick enough to pipe and hold its shape.
Pipe onto the baking tray - I use a piping bag with a large hole cut from the bottom so less squeezing is need when piping.
Bake for 15 minutes. Open the oven door and slam closed to release some air and continue baking for a further 3 minutes.
Remove from the oven and prick the bases of the eclairs with a clean kntting needle or sharp knife. Place back in the oven and continue to bake for another 3 minutes until golden and hollow sounding when you knock them.
Allo to cool fully and slice down the centre and allow to cool on a wire rack. I don't always fully slice but that is personal choice.
Whisk the double cream until thickened and pipe into the cooled eclairs.
Melt the chocolate in a Pyrex bowl over a pan of boiling water (Do not allow the base of the bowl to touch the boiling water or it will burn).
When the chocolate is melted, stir in the remaining butter and stir until melted and mixed through thoroughly.
Leave to cool slightly and spread over the tops of the eclairs.
Decorate with marzipan leaves and eat the same day.