Preheat your oven to 350°F (175°C).

Do not grease your angel food cake pan.

In a mixing bowl, beat the egg whites until foamy.

Add the cream of tartar and salt to the egg whites.

Gradually add in the granulated sugar while beating until stiff peaks form.

Gently sift the gluten-free flour over the egg whites and fold it in with a rubber spatula.

Fold in the vanilla extract.

Pour the batter into the prepared pan and smooth the top.

Bake for 30 minutes or until golden brown and a toothpick comes out clean.

Allow the cake to cool upside down in the pan.