Preparation

1. Preheat oven to 325˚F.
2. Sift ¾ cup of the sugar together with the cake flour in a mixing bowl and reserve.
3. Stir together vanilla, espresso powder, and Kahlúa® in a small bowl and reserve.
4. Place egg whites in Cuisinart™ mixing bowl. Insert the chef’s whisk. Turn to speed 9. After 30 seconds add cream of tartar and salt and increase to speed 12 until soft peaks form, about 1 minute 15 seconds. Slowly add remaining ¾ cup of granulated sugar and continue to mix on speed 12 until the peaks are firm and glossy, about another 30 seconds. Remove bowl from stand mixer.
5. Gradually sift the reserved fl our/sugar mixture into the whites and carefully fold in with a large rubber spatula. Fold in the espresso mixture. Be gentle when folding but at the same time make sure all ingredients are evenly incorporated.
6. Spoon batter into an ungreased 9-inch tube pan. Smooth and even the top by spreading with a rubber spatula.
7. Bake in preheated 325°F oven for 40 to 45 minutes, until a cake tester comes out clean. Invert pan onto the neck of an empty long-necked bottle (such as a wine bottle) and allow to cool completely.
8. To remove cake from pan, slide the tip of a long, narrow knife between the cake and the pan. Cover the pan with a plate and invert it. Slide the knife along the bottom of the pan until it is free.