Preheat oven to 350 degrees F.
Separate the egg whites into a large, clean mixing bowl and set aside for at least 30 minutes.
In a small mixing bowl, mix together gf flour, arrowroot powder and 3/4 cup of powdered coconut sugar.
Sift flour mixture.
In the bowl with the egg whites, mix in cream of tartar and salt.
Beat egg white mixture on low speed until foamy.
Add vanilla and almond extracts.
Increase the speed of the mixer until egg white mixture thickens and increases in size.
Beat in the remaining powdered coconut sugar a little at a time continuing to beat until the merengue holds stiff peaks.
Gently fold in flour mixture a little at a time and mix until is just blended. Don't over mix!
Spoon mixture into round angel food cake pan.
Remove air bubbles by dropping pan gently on the countertop.
Bake for 45 minutes (cake is done when it springs back after being gently pressed on)
Remove cake from oven and invert over a glass bottle (for mine, I placed the rim of the pan on two mason jars)
Allow to cool for 2 hours.
Run a knife around the edge of the baking pan to help loosen.
Remove the cake and place on a plate.