Ensure that all the ingredients are very cold before starting.

Pulse the butter, flour (and sugar if making a sweet pastry) in a food processor until it has the consistency of breadcrumbs.

Alternately, rub in the cold butter with two knives or a pastry cutter. Try not to use your hands as it will warm up the butter.

Add the egg and cream or iced water and mix until just combined.

Bring the pastry into a ball and flatten into a disk on a piece of cling wrap. This makes it easier to roll into a round shape later.

Chill and rest the pastry for about 30 minutes before use.

Switch on the oven and pre-heat to 200 degrees celcius.

Roll out the pastry and line a tart pan ensuring that the pastry overlaps the sides a bit as it may shrink during baking if not rested enough. I chilled it again for another 10 minutes before baking.

Prick the base and line with parchment paper and baking beans or beans, and bake blind for about 10 minutes.

Remove the baking beans and bake for another five minutes. Be careful not to get a burn as you may drop the beans and damage the tart case.