Slice lemons, with rind still on, as thinly as possible (preferably paper-thin); place in a bowl. Add 2 cups (500 mL) sugar and let stand, stirring occasionally, until sugar is well absorbed, at least 2 hours, but overnight is best.

Roll out pastry to line pie plate. Beat eggs well; add nutmeg, if using. Arrange layers of lemon slices and their juice over the unbaked pastry, sprinkling each layer with extra sugar as you go. Pour egg mixture over all.

Roll out remaining pastry and place over filling, crimping the edges. Cut vents in centre. Paint crust with milk and sprinkle with sugar. Bake at 450ºF (230ºC) for 10 minutes. Reduce heat to 350ºF (180ºC) and bake 35 minutes more, or until a knife inserted into centre comes out clean.

Chill before serving. Makes 6 to 8 servings.