1/2 cup sweetened flaked coconut
12 large egg whites
1 cup cake flour
1 tsp cream of tartar
1.5 cups sugar
2 tsp pure vanilla extract
1/4 tsp salt
1 tsp coconut extract
Preheat the oven to 325F. Have ready a 9-inch ungreased angel food tube pan with a removable bottom. Place the coconut in the bowl of a food processor and process until finely ground. Set aside.
Combine the flour, 3⁄4 cup sugar, and salt in a medium mixing bowl and whisk thoroughly to break up any lumps. Set aside.
Place the egg whites in a large mixing bowl and whip them with an electric mixer fitted with a whisk attachment on medium speed until frothy. Add the cream of tartar and continue to beat on medium speed until the egg whites begin to turn white.
With the mixer still on medium speed, pour in the remaining 3⁄4 cup sugar in a slow, steady stream and whip until the whites are shiny white and just hold soft, floppy peaks when the whisk is lifted from the mixture.
Stir in the vanilla and coconut extracts until just mixed in.
Place a small fine-mesh strainer over the bowl of egg whites and strain about 1⁄4 cup of the flour mixture into the egg white mixture. Gently fold in the flour mixture with a rubber spatula.
Repeat with the remaining flour mixture in 1⁄4-cup increments until all of it has been folded in. Gently fold in the coconut.
Pour the batter into the tube pan and smooth the top with a rubber spatula. Bake the cake until it is golden brown, about 50 minutes.
Remove the pan from the oven. If your pan has feet, invert the pan onto a heatproof surface and allow it to cool.
If your pan doesn’t have feet, invert 4 heatproof drinking glasses on the counter and rest the inverted pan on top of the glasses to allow air to circulate around the cake while it cools. Let the cake cool in the pan for at least 1 hour or up to 6 hours.
To remove the cake from the pan, run a sharp paring knife around the edges, being careful to leave the golden crust intact. Remove the sides of the pan. Invert the cake onto a serving platter.
Run the paring knife under the removable bottom of the pan and lift it off the cake. Slice and serve. Store uneaten cake in a cake keeper or wrap in plastic and store at room temperature for up to 3 days.