Next, make the filling.
Put the egg yolks and sugar in a bowl and whisk to combine.
Pour in the cream, mix well and then strain the mixture through a fine sieve into a heavy pan.
Warm over a low heat to blood temperature (98.6°F), stirring all the time. Put into a jug.
Put the cooled pastry case, still in the ring, in the parchment-lined pan, on the middle shelf in the oven.
Slowly and carefully pour in the custard, filling the case as full as you can – right to the very top.
Grate nutmeg liberally all over, to cover the custard completely.
Bake the tart for 45-50 minutes until the custard looks set but not firm – it should have a slight, even quiver across the top when you gently shake the roasting pan.
Leave to cool to room temperature, then remove the ring. Cut into neat wedges with a sharp knife to serve.