Heat the oven to 325°F. Have ready a 9-1/2- or 10-inch tube pan with sides at least 3-3/4 inches high.
In a large bowl, sift together the cake flour, 1 cup of the sugar, the baking powder, salt, and cinnamon. Make a well in the center and put in the oil, egg yolks, water, and vanilla. Beat the mixture on medium speed until smooth and thick and it turns a light tan color, at least 3 minutes. Set aside.
In a large, clean bowl with clean beaters or a whisk attachment, whisk the egg whites and the cream of tartar on medium speed until the cream of tartar is dissolved and the whites are foamy. Increase the speed to high and beat the whites until the movement of the beaters forms lines in the mixture. Slowly pour in the remaining 1/2 cup sugar, about 2 Tbs. at a time, and beat the mixture until soft peaks form.
With a large rubber spatula, stir about one-third of the egg whites into the yolk mixture. Gently fold in the remaining egg whites until no white streaks remain. Pour the batter into the tube pan, spreading it evenly. Bake until you can gently press your fingers on top of the cake and it feels firm, about 1 hour and 10 minutes. Any cracks that form on the top should look dry.
Invert the pan onto a bottle with a narrow neck and let cool thoroughly, about an hour. Use a small, sharp knife to loosen the cake from the sides of the pan and the center of the tube, if necessary. Remove the cake from the pan and slide it onto a serving plate. Sprinkle the top with the confectioners’ sugar and cinnamon mixture.