Place rack in the bottom third of your oven and set to 350F. You'll be using an angel food cake pan for this recipe but there is NO NEED to prep the pan, so no buttering and flouring etc.
Separate the egg whites into a bowl or liquid measuring cup. The best practice is to separate the egg whites one-by-one into a small bowl, transferring the whites to your larger bowl or measuring up as you go. This way there's no heartache if a yolk breaks.
You have two choices for the dry ingredients. If you have a food processor handy go ahead and add half the super fine sugar and all the cake flour to the bowl of your processor and whiz, whiz whiz. Then sift the mixture into a bowl and set aside. If you don't have a processor or just don't feel like using it then sift the flour and sugar into a bowl five or six times.
Pour the egg whites, cream or tartar, salt, and vanilla into the CLEAN bowl of your stand mixer fitted with a whisk attachment. Run on low then increase speed to medium-high.
Once the egg whites become frothy you can sprinkle the remaining sugar in a tablespoon at a time. It's VERY important to add the sugar in slowly with the mixer running, if you dump it in too fast you'll never get a thick, luscious meringue.
After you reach the stiff peak stage it's time to fold in the dry ingredients. Add about 1/4 cup of the dry mixture at a time and fold in with a spatula. Cut down the middle of the bowl and bring the spatula back up, scraping the side as you go, turn the bowl slightly and repeat until the flour and sugar is incorporated. Repeat until there is no dry mixture left.
Transfer the batter to your cake pan and run a knife or skewer through a few times to help break up any air bubbles hiding in the batter.
Bake at 350F 35-40 minutes or until a the cake is golden brown and a skewer inserted in the center comes out clean.
Invert onto the counter and allow to cool upside-down for about an hour. Most angel food cake pans have feet at the top so the cake can cool upside down but if yours doesn't just invert onto a wire rack.
Once the cake is completely cooled run a thin knife along the inner and outer edge then pull the center piece out. Run the knife along the bottom of the pan and invert onto a cake stand. Serve alone or with whipped cream and berries.
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Notes
Measure your flour correctly! Adding too much flour to the recipe is the most common mistake. The best, and easiest way to measure flour is by using a scale. If you don't have one then fluff your flour with a spoon, sprinkle it into your measuring cup, and use a knife to level it off.
DON'T grease/butter/oil your cake pan! The batter needs to cling to the wall of the pan to rise properly.
If you don't have cream of tarter you can use an equal amount of white vinegar or lemon juice to stabilize the egg whites.
Super fine sugar is amazing for meringues but if you can't find it either whiz regular granulated sugar in the food processor or use it as is and just make sure to sprinkle in ever so slowly.
Take care when folding in the dry ingredients. You're incorporating them gently being careful not to crush the air bubbles in the meringue.