Adjust the oven rack to the lower-middle position, and preheat oven to 325 degrees F. Line the bottom of a 16-cup tube pan with parchment paper, but do NOT grease. If you are using a tube pan with a removable bottom (like an angle food cake pan), then you do not need to line it with parchment paper.

In a large bowl, add the sugar, cake flour, baking soda, and salt. Whisk to combine.

In a medium bowl, add the 5 separated egg yolks, 2 whole eggs, lemon zest, lemon juice, water, oil, and vanilla extract. Whisk to combine well.

Slowly whisk the egg mixture into the flour mixture to make a thick batter.

In a large mixing bowl, using a hand mixer (or a stand mixer), beat the separated egg whites and the cream of tartar together on medium-high speed, until the egg whites are beat stiff, 2 to 4 minutes.

Fold the whipped eggs whites into the batter with a large rubber spatula.

Scrape the cake batter into the prepared pan, and smooth the top. Wipe any drips of batter from the side of the pan, and then gently tap the cake pan on the counter a few times to settle the batter.

Bake until the top of the cake is golden brown and springs back when firmly touched, about 50 to 60 minutes.

Remove the cake from oven, and invert the cake pan over a sturdy bottle or a metal kitchen funnel (or if your cake pan has "feet" that go above the top of the pan, simply rest the cake upside down). Let the cake cool completely, upside down, for 2 to 3 hours.

Once cool, run a small knife around the edge of the pan to loosen, and gently tap upside down to release the cake. Remove the parchment paper, and place the cake right side up on a serving platter. (If you used an angel food cake pan, run the small knife around the edge, remove the bottom, run the knife around the bottom, and then remove the cake).

Serve plain, with a light dusting of powdered sugar or with a glaze.