Preheat the oven to 200C/400F/Gas 6.
For the pumpkin mixture, place all the ingredients into a food processor and blend to mix.
For the pie, place the pastry disks onto a baking sheet.
Place the pumpkin mixture carefully onto the pastry disks, and transfer into the oven for 10 minutes.
For the chocolate sauce, heat the condensed milk in a saucepan over a medium heat until it thickens.
Add the cream and melted chocolate and stir until smooth.
To serve, place the pies onto serving plates, then drizzle the chocolate sauce and sprinkle over the chopped nuts.