-
1
Rub the cold butter into the flour and icing sugar until the mixture resembles coarse breadcrumbs. Add the egg yolk and bring the dough together without overworking. Wrap and rest in the refrigerator until firm — the dough should hold a clean edge when pressed.
-
2
Press or roll the pastry into individual tart tins, ensuring an even thickness throughout. Blind-bake the shells at 180 °C for 8 minutes, until the base is set and just beginning to colour — this prevents a soggy base beneath the custard.
-
3
Dissolve the caster sugar in the warm milk and evaporated milk, then allow to cool slightly. Beat in the eggs gently. Strain the custard through a fine sieve at least twice, removing every strand of membrane, until the liquid runs perfectly smooth and clear. This is where the dish lives or dies: any egg membrane left in the mixture will create visible lumps in the finished tart, and no subsequent step can correct it.
-
4
Pour the strained custard into the par-baked shells, filling to just below the pastry rim. Transfer to the oven at 160 °C. Bake until the custard surface is burnished and golden but the centre retains a distinct wobble — high heat at this stage will cause the custard to puff, bubble, and pit.
-
5
Remove the tarts from the oven while the centre still trembles. Rest on a rack; the custard will set fully and reach its definitive silky texture as it cools to just above room temperature. The finished tart yields to light pressure like barely set jelly — firm at the edge, yielding at the heart.