Fit the K beater to the machine.
Grease the tart tin.
Add Ingredients 1 (butter, flour, salt, sugar) into the Mixer bowl.
Attach the Mixer bowl to the machine and fit the splash guard.
Mix on speed 2 for about 2 minutes or until coarse crumbs are formed.
Add Ingredients 2 (egg) into the Mixer bowl, while the machine is running.
Mix on speed 2 for 2 minutes.
Transfer the contents of the Mixer bowl to a worksurface.
Wrap with plastic wrap.
Chill in the fridge for 30 minutes.
Transfer the dough to a lightly floured worksurface.
Roll the dough out to about 5 mm thick.
Line the tart tin with the pastry dough.
Trim the excess pastry and prick the base with a fork.
Pre heat the oven to 190ºC.
Line the tart tin with parchment paper.
Fill with baking beans.
Bake for 15 minutes at 190°C.
Remove the parchment paper and baking beans from the tart tin.
Brush Ingredients 3 (egg) over the pastry.
Bake for 5 minutes at 190ºC.
Leave to cool.
Reduce the oven temperature to 180ºC.
Add the first item of Ingredients 4 (golden syrup) to the saucepan.
Heat on a low heat until warm.
Add the last 2 items of Ingredients 4 (breadcrumbs, lemon zest) to the saucepan.
Stir until combined.
Transfer the contents of the saucepan to the tart tin.
Bake for 25 minutes at 180ºC.