Arrange an oven rack to the lower third position and preheat the oven to 350°F (180°C). Sift together the cake flour, powdered sugar, and salt four times to ensure a light texture. Set this mixture aside for later use.

Wipe the bowl and whisk attachment of an electric mixer with a paper towel and a little lemon juice to remove any grease. Add the egg whites and beat on the lowest speed until frothy, about 30 seconds. Sprinkle in the cream of tartar and continue beating on medium speed until the egg whites thicken slightly and swirl lines appear, about 1 minute. Gradually add superfine sugar, one tablespoon at a time, and beat until the mixture forms soft to medium droopy peaks, about 1-2 minutes. Beat in the vanilla bean paste, almond extract, and a few drops of pink food coloring, if using.

Remove the bowl from the mixer. Sift the dry ingredients (from Step 1) over the meringue (from Step 2) in four additions, folding gently but thoroughly with a spatula after each addition. Carefully transfer the batter into an ungreased 10-inch angel food cake pan and smooth the top with a small offset spatula. Bake on the lower rack of the oven for about 35 minutes, until the top springs back when lightly touched and a skewer inserted in the center comes out clean. Avoid opening the oven before the baking time is complete to prevent the cake from deflating.

Remove the cake from the oven and immediately invert the pan onto a wire rack to cool upside down for one hour. After cooling, loosen the sides and center of the cake with a thin metal spatula or knife, and carefully lift the cake from the pan. Let it cool completely on the wire rack before proceeding. I like to let the cake cool fully and undisturbed—it helps maintain its delicate, fluffy structure.

Wipe the bowl and whisk attachment of a stand mixer with a paper towel and lemon juice to remove any grease. In the bowl, combine egg whites, granulated sugar, light corn syrup, cream of tartar, and a dash of salt. Place the bowl over a pot of simmering (not boiling) water and whisk gently but constantly until the mixture reaches 130°F (54°C) on a candy thermometer. Transfer the bowl back to the stand mixer and beat on low speed for 2 minutes, medium for 2 minutes, and then on high speed until the frosting is very thick and glossy, about 5 minutes. Beat in the vanilla bean paste and a few drops of pink food coloring, if using, until well combined. Use the frosting immediately for the best texture. For an extra pretty finish, I sometimes add a teensy bit more food coloring to make the color pop.

Place the cooled cake wide end down on a cake plate or pedestal. Pile the pink marshmallow frosting (from Step 5) onto the top, spreading it from the top down the sides with a metal spatula. Use the back of a spoon to create decorative swirls in the frosting. Sprinkle the top with rainbow nonpareil sprinkles or your preferred choice of decorations. To make the cake even more festive, I like to add extra sprinkles right before serving for a little extra crunch.