Step 1

To make cake: Preheat oven to 350 degrees F. Sift flour, 3/4 cup granulated sugar, baking powder and salt into a small bowl; set aside.

Step 2

Beat egg whites and cream of tartar in the bowl of an electric mixer just until soft peaks form. Beat in the remaining 3/4 cup granulated sugar, 2 tablespoons at a time, until the whites are shiny and form soft peaks.

Step 3

Whisk together egg yolks, orange liqueur, orange, lemon and lime zests, lemon and lime juices, and vanilla in a small bowl. Pour over the egg whites and fold together with a rubber spatula.

Step 4

Resift the reserved dry ingredients over the beaten egg whites in four parts, folding in gently after each addition. Spoon the batter into an ungreased 10-inch angel food cake pan with a removable bottom. Smooth the top and run a knife or spatula through the batter to remove any air bubbles. Bake until the top is golden and a long skewer inserted into the cake comes out clean, 45 to 50 minutes. Invert the pan over the neck of a bottle and let cool completely.

Step 5

To prepare citrus glaze: Use a citrus zester to remove long threads of zest from the orange, lemon and lime; set aside. Squeeze 4 teaspoons of juice from each of the fruits. Whisk the juices into the confectioners' sugar in a small bowl to make a smooth glaze.

Step 6

Loosen the edges of the cake with a knife and invert onto a cake plate. Spoon the glaze over the top, allowing it to drip down the sides. Sprinkle the top of the cake with the julienned zest. Let the cake stand at least 30 minutes for the glaze to set.