A must have cake recipe! Homemade angel food cake is much better than store-bought or mixes. It's light and fluffy as a cloud, it has the perfect vanilla bean flavor, and it's the perfect base to your favorite sauces and toppings.
Preheat oven to 350 degrees. In a food processor, pulse sugar until super fine, about 2 minutes.
In a mixing bowl, sift together half of the sugar, the cake flour and the salt.
In a separate large mixing bowl, whisk together egg whites, water, vanilla beans, vanilla extract and cream of tartar until well combined, about 2 minutes (the vanilla beans may not separate but that's fine, once sugar is added they should separate).
Switch to a hand mixer and whip mixture on medium speed while slowly adding remaining sugar to mixture, until medium peaks form**.
Sift just enough of the flour mixture in to evenly dust the top of the egg white mixture and using a spatula gently fold flour layer into egg white mixture and continue this process until all of the flour mixture has been incorporated (be sure to work gently with batter so it doesn't deflate and add small amounts of flour mixture at a time).
Gently spoon the batter evenly into an ungreased angel food cake pan (do NOT grease the pan, the cake won't rise properly if you do. If you are looking for a good angel food cake pan I have this one here).
After 35 minutes begin to check for doneness by inserting a wooden chopstick or skewer halfway down through the cake, it should come out clean*** (mine took 40 minutes).
Remove cake from oven and cool upside down on a wire rack (do not leave it upright, it will start to deflate like mine did a little while I was taking pictures. If the pan has feet no need to use the wire rack).
Cool at least 1 hour before removing from pan (I ran a sharp knife around the edge to loosen). Cut into slices and serve with whipped cream and strawberries (or fruit sauce, chocolate sauce or topping of choice).
*Whites and yolks will separate better with fresher eggs. I separated the whites from the yolks while still cold (because warmer eggs are harder to separate) then let them rest in a bowl, covered to come to room temperature (about 30 minutes). Work with one egg at a time separating and dropping into a small bowl first to make sure that egg didn't get any bit of yolk in it - then dump it into the main bowl. This just helps ensure you won't ruin it from one drop of yolk. If one of the yolks does break on one of them then reserve it for a different use.
*Be sure to use clean bowls and mixing equipment as an oily bowl could ruin the batter. Also don't use the whites in the carton for this recipe. And if you live in a climate with high humidity you may want to cut back on the water a 1 - 2 tablespoons just to ensure you'll be able to whip up the whites properly.
**If you aren't sure quite what "medium peaks" refers to this picture will you give an idea. You want peaks that stand but droop. Be patient with them they do take quite some time to whip up.
***If you find the top is browning too much you can place one of the oven racks above the cake, without letting it touch the top, and lay a sheet of foil over the rack just above the cake, not directly on the cake or it will stick.