Preheat oven to 350F degrees (160C). Line cupcake
tin with liners, set aside.
Using an electric mixer with whisk attachment
combine egg whites, cream of tartar, vanilla
extract and salt in a large bowl. Blend on medium
speed for 4-5 minutes until stiff peaks form.
Gradually add in sugars and continue to blend
until just combined. By hand fold in cake flour.
Pour batter into cupcake liners filling ¾ full.
Bake for 15-18 minutes until cake tester comes out
clean and top is firm. Do not overbake.
Cool on wire racks completely before frosting.