For the pastry
Preheat the oven to 200°C.
Put the flour, sugar and salt in a bowl.
Rub the butter between your fingers into the dry ingredients, until the mixture looks like breadcrumbs.
Add the egg yolk and water and bring mixture together to form a dough.
Don't handle the pastry more than necessary.
Cover with cling film and leave to rest in the fridge for 30 minutes, before rolling out and lining a 26 cm loose-bottomed tart tin.
Bake blind for 10 - 12 minutes.
Remove from oven and remove the baking aids, i.e. baking paper and baking beans.
Reduce oven temperature to 180°C.
Heat the cream, milk, cinnamon and cardamom in a pan until just below boiling point and turn off the heat.
Whisk the eggs, yolks and sugar together.
Strain the cream mixture onto the eggs and whisk lightly to combine, discarding the cinnamon and cardamom.
Stir the ground nutmeg, salt, butter and vanilla essence into the mixture and pour into the pre-baked pastry case.
Bake for 25 - 35 minutes or until the custard is firm.
Sprinkle a little ground nutmeg over the top of the tart and serve at room temperature.