Place the oven rack one position below the middle and preheat the oven to 375-degrees
Sift the flour together with ¾ cup of the cake flour five (5) times. Don't skip this step!
Combine the egg whites with the kosher salt in a large mixing bowl. Beat using the whisk attachment on medium-high speed until the egg whites are foamy.
Add the cream of tarter and continue beating until soft peaks form - about 2 to 3 minutes. Do not beat until the egg whites are dry or they will “break”.
Slowly pour in the remaining 1 cup of sugar and beat into the egg whites on low speed. Scrape down with a spatula to make sure all the sugar and egg whites are well blended.
Mix the vanilla and the almond extracts into the egg whites.
Gently sprinkle the flour mixture over the top of the egg whites and mix in using low speed just until the flour is blended into the batter – about 1 minute.
Pour the batter into an ungreased tube pan (one with a removable bottom). Using a spatula or knife run it through the batter to break up any large bubbles.
Bake the cake in a 375-degree oven, on the rack slightly below the middle.
Bake for 30 to 35 minutes or until the cracks on top of the cake appear dry. Do not open the door until the cake is done.
Remove and immediately invert the cake. If your pan doesn’t have supports, a wine bottle works well for this. Check to make certain the opening of the tube fits over the neck of the wine bottle. Allow the cake to cool completely, 2 to 3 hours.
To remove the cake from the pan, take a long, thin knife and gently run it around the edges to loosen it from the pan. Flip the cake over onto a cake plate and gently run the knife betweenthe bottom of the pan and the cake to release it.