This decadent Angel Food Coconut Cake is the perfect complement to any celebration!
Preheat oven to 325 degrees F, with rack in the lower third of oven.
Beat egg whites and warm water with a mixer on low speed until foamy, about 3 minutes. Add cream of tartar, vanilla, salt, and coconut extract.
With machine running, add remaining 3/4 cup sugar, a little at a time. Increase speed to high, and beat until peaks are stiff and glossy, about 2 minutes.
Working in 3 batches, sift flour mixture over egg-white mixture, gently folding in each addition with a rubber spatula, being careful not to deflate egg whites.
Immediately from the oven, carefully invert pan onto a wire rack. Let cake cool in pan, about 1 hour.
Pour the heavy cream into a chilled stand mixer bowl (to chill a bowl fill with water and ice and let sit for a moment, then empty and dry) and add the sugar and coconut extract.
Gently frost the cooled angel food cake and sprinkle with unsweetened coconut flakes. (Or sweetened if you prefer!)