Make the pastry: in a large bowl combine the All-Purpose Flour and a pinch of Salt.
Cut cold Unsalted Butter into small cubes and work it into the flour with your fingertips (or pulse briefly in a food processor) until the mixture resembles coarse crumbs.
Add the Egg Yolk and a few tablespoons of cold Water, mixing gently until the dough just holds together; do not overwork. Form into a disk, wrap and chill for at least 30 minutes.
Preheat the oven to 190°C (375°F). Roll the chilled dough on a lightly floured surface to fit a 9-inch tart pan, press it in, trim the edges, and chill the lined pan for 10 minutes to prevent shrinking.
Blind-bake the crust: prick the bottom with a fork, line with parchment and fill with baking weights or dried beans. Bake for 15–20 minutes, remove the weights and parchment, and bake 5–8 minutes more until lightly golden. Reduce oven temperature to 180°C (350°F) if you prefer a slightly gentler finish.
While the crust bakes, cook the Lardons in a skillet over medium heat until browned and crisp; drain on paper towels.
Make the custard: in a bowl whisk the Eggs until smooth, then whisk in the Crème Fraîche and Milk until fully combined.
Season the custard with a little more Salt (if needed), freshly ground Black Pepper, and a light grating of Nutmeg; taste and adjust.
Assemble and bake: spread the cooked lardons evenly over the blind-baked crust, pour the custard mixture over them, and gently shake to level.
Bake the quiche at 180°C (350°F) for 25–35 minutes, until the filling is set but slightly wobbly in the center and the top is lightly golden.
Let the quiche rest for 10–15 minutes before slicing so the custard firms up; serve warm or at room temperature.
