Preheat your oven to 350 degrees. This temperature is key to ensuring even baking.
In a medium bowl, whisk together the cake flour, granulated sugar, and salt until well combined. This helps to incorporate air and ensure an even flavor throughout the cake.
In a large bowl, use an electric mixer to beat the egg whites along with the cream of tartar, vanilla extract, and almond extract for about 5 to 7 minutes. You want to beat them until stiff peaks form, meaning they will stand up straight when you lift the beater out of the bowl.
Once the egg whites are ready, gently fold the dry ingredients into the egg white mixture using a rubber spatula. Be careful not to deflate the egg whites as you do this; a gentle touch is essential.
Pour the batter evenly into an un-greased angel food cake pan. It’s important not to grease the pan, as this allows the cake to climb up the sides and achieve its characteristic height.
Bake for about 40 minutes, or until the top is golden brown and there are cracks visible. The cake should spring back when touched lightly. Keep an eye on it as it bakes to ensure it doesn't over-bake.
Once baked, remove the cake from the oven and immediately invert the pan upside down. Let it cool completely in this position. This helps maintain the cake's height and prevents it from collapsing.
After it's cooled, run a spatula around the edges to loosen the cake from the pan. Carefully remove it and place it on a serving plate.
If desired, top the cake with the blueberry pie filling for added flavor and a burst of color. Serve immediately and enjoy!
