Bring a large pot of water to a boil. Meanwhile, grease a 9- by 13-inch glass baking dish with 1 tablespoon butter, then dust with flour, shaking out excess. Preheat oven to 350° F.

Add corn to the pot of boiling water and turn off the heat. Remove from water after about 5 minutes and let cool.

Cut the kernels from the cobs; you should have about 3/4 cup.

Melt remaining 2 tablespoons butter in a small saucepan over medium heat. Whisk in flour and cook for 2 minutes, stirring. Slowly stir in milk. Cook for about 5 minutes, stirring constantly, until the sauce thickens.

Slowly whisk in egg yolks. Cook for 3 minutes, stirring constantly. Add half-and-half, salt, pepper, sugar and nutmeg, stirring to combine. Fold in corn kernels. Transfer to a mixing bowl and set aside.

Beat egg whites until soft peaks form. Add half the whites to the corn mixture, folding to combine.

Beat remaining whites until stiff peaks form. Fold into corn mixture. Transfer to the prepared baking dish and bake for 20 to 25 minutes, until the top has lightly browned and the filling is set.