Mix the butter and sugar together until they are smooth then stir in the egg yolk. Add the flour and salt unt mix until it resembles fine bread crumbs.

Press the mixture into a pie in and refrigerate it for at least an hour until it is firm.

Meanwhile, pre-heat the oven to 175C(347F) and then bake the shortbread for 20-22 minutes, rotating half way through, until it is golden.

Cool the crust completely on a wire rack still in the tin.

Pre-heat the oven to 180C(356F) fan-forced.

Cut the pumpkin in half and scoop out the seeds. Place it cut side up on a lined baking tray and bake them for 30 minutes or until a knife can be inserted easily. When cooked, let them cool a bit then scoop the flesh into a blender or food processor and process until smooth.

Refrigerate the puree until it is cool.

Preheat oven to 160C(325F) degrees. Put all the ingredients in a bowl (except the crust and ice-cream) and whisk it together until it's smooth.

Pour the mixture into the shortbread crust.

Bake the pie for an hour or until it is firm but still has a little wobble in the middle.

Leave it to cool on a wire rack and then transfer the fridge for at least 6 hours.

Serve it chilled with vanilla ice-cream.

Mix everything together and store it in an air-tight container.