How to Make It
Heat oven to 400° F.
On a lightly floured surface, roll the pastry dough into a round about 13-inches in diameter. Lower dough carefully into a deep 9-inch pie dish, pressing it into place gently with your fingers. Trim excess dough, leaving a ½-inch overhang all around. Crimp the edges decoratively.
Line the dough with a piece of foil, leaving an overhang all around. Fill with dried beans or pie weights and bake for 10 minutes, until just faintly golden. Remove from oven and let rest as you prepare filling.
In a medium bowl, combine apricots, 1 tablespoon lemon juice, and 4 tablespoons sugar. Set aside and let macerate at room temperature for 20 minutes, then drain off all but 2 tablespoons of liquid and toss with cardamom and nutmeg. Spoon mixture into the bottom of the prepared pie crust, spreading it out in an even layer.
Using an electric mixer, cream the butter, sugar, and egg yolks in medium bowl until pale and thick. Gently stir in the salt, the flour, remaining lemon juice, lemon zest, and milk.
Making sure your mixer is clean and dry, add egg whites to a large bowl and whip them to stiff peaks, then gently fold them into the butter mixture. Spoon the batter into the pie dish, smoothing it out so that it blankets the apricots and covers fully to the edge of the crust.
Bake for 8-10 minutes, until the top begins to brown, then reduce the temperature to 350°F and bake another 30 minutes or until the sponge is set. Remove from oven and cool completely before serving.