Ube Chiffon Cake

Preheat the oven to 350°F.
In a medium bowl, beat the egg whites, 50 g white sugar and cream of tartar until stiff and glossy peaks formed. You should be able to hold your bowl upside down without the egg whites falling out.
In a separate bowl, whisk together the egg yolks, the rest of the white sugar, salt, water and oil until combined.
Add the ube mash and beat until blended and smooth. Gradually sift in the flour and beat in mixer until smooth.
Take about half of the egg white mixture and fold it into the batter (stir in the same clockwise motion with a spatula) until no egg white streaks remain. Then add in the remaining egg whites and fold until no streaks remain.
Pour the batter into the ungreased 7-inch angel food cake pan.
Put cake in oven and bake for about 25-30 minutes until the cake’s surface is golden brown. When you touch the cake it should spring back.
Remove cake from the oven and revert the cake pan upside down on top of a plate to finish cooling and rising. The cake should still remain in the pan.
When the cake is completely cooled, gently run a plastic knife around the rim of the cake and then remove cake from pan.