For Sponge Cake: Preheat oven to 450 degrees F (230 degrees C) and place oven rack in the center of the oven.   Butter, or spray with Pam, a 17 inch (43 cm) x 12 inch (30 cm) baking pan, line it with parchment paper, and then butter and flour the parchment paper (or spray with Baker's Joy).  Set aside.

While eggs are still cold separate two of the eggs, placing the yolks in one large mixing bowl and the whites in another bowl.  To the two yolks, add the additional yolk, and the two remaining eggs.  Cover the two bowls with plastic wrap and allow the eggs to come to room temperature before using (about 30 minutes).

Meanwhile, in a small bowl whisk together the sifted cake flour and cornstarch.  Set aside.

Once the eggs are at room temperature, place the egg yolks, along with 1/2 cup (100 grams) of granulated white sugar, in your electric mixer, fitted with the paddle attachment.  Beat on high speed for five minutes, or until thick, pale yellow, and fluffy.  (When you slowly raise the beaters the batter will fall back into the bowl in slow ribbons.)  At this point beat in the vanilla extract.

Sift half the flour mixture over the egg yolk mixture and fold in gently with a rubber spatula, just until the flour is incorporated.  Sift the remaining flour mixture into the batter and fold in.

In a clean mixing bowl, with the whisk attachment, beat the egg whites until foamy.  Add the cream of tartar and continue beating until soft peaks form.  Sprinkle in the remaining one tablespoon (13 grams) granulated white sugar and beat until stiff peaks form.  Gently fold a little of the whites into the batter to lighten it, and then add the rest of the whites folding just until incorporated.  Pour the batter into the prepared pan, evenly spreading the cake batter with an offset spatula or knife.

Bake for about 7 minutes or until golden brown. A toothpick inserted in the center will come out clean and the cake, when lightly pressed, will spring back.

Immediately upon removing the cake from the oven invert the sponge cake onto a clean dish towel that has been sprinkled with confectioners sugar.  Carefully remove the parchment paper, sprinkle lightly with confectioners (powdered or icing) sugar, and roll up the sponge, with the towel, while it is still hot and pliable. Place on a wire rack to cool. 

Meanwhile for the Raspberry Puree (if using): Thaw the unsweetened frozen raspberries in a large fine meshed strainer suspended over a large bowl.  (This may take a few hours.)  Once the berries have completely thawed, force the juice from the berries by gently pressing the berries with the back of a large spoon.  All that should remain in the strainer is the raspberry seeds.  Throw away the raspberry seeds and, to the strained juice, stir in the lemon juice (if using) and 1/4 cup (50 grams) of white sugar (add more if needed).  The puree can be stored in the refrigerator for a week or frozen for up to a year.

For Raspberry Whipped Cream:  In a large mixing bowl place the whipping cream, vanilla extract, and sugar and stir to combine. Cover and chill the bowl and beaters in the refrigerator for at least 30 minutes. When chilled, beat the mixture until soft peaks form. Then add the sweetened raspberry pur? or raspberry jam, a little at a time, and beat just until stiff peaks form when the beater is raised. Taste and fold in more sugar or puree, if needed.

To Assemble: Remove about 1/2 cup of the raspberry whipped cream to use as garnish.  Then unroll the sponge, spread with the remaining whipped cream filling, and reroll.  Transfer to your serving platter.   Place the remaining whipped cream in a pastry bag fitted with a decorative tip and pipe rosettes down the center of the sponge.  Place fresh raspberries on the rosettes, if desired.  Cover, and chill in the refrigerator for a few hours or overnight.  (You can serve this cake immediately but chilling it for a few hours, or even overnight, sets the filling and makes it easier to slice.)  Just before serving, dust with confectioners (powdered or icing) sugar.

Serves 6 - 8 people.

Adapted from the Cake Bible by Rose Levy Beranbaum