Mile High Frosting

Combine egg whites and jelly or corn syrup in a heatproof mixing bowl. Place the bowl over a pot of simmering water (double boiler method), ensuring the bottom does not touch the water.

Whisk the mixture continuously while heating, breaking up the egg whites and blending them smoothly with the syrup.

Continue whisking until the frosting reaches stiff peaks and becomes glossy and thick, about 5-7 minutes total heating time.

Remove the bowl from heat and let cool slightly, about 1-2 minutes.

Add vanilla extract and whisk until fully incorporated.

Use the frosting immediately while it is still warm and fluffy, spreading it generously onto cooled cake layers or cupcakes.