This recipe for marshmallow filling is courtesy of chef Sebastien Rouxel of Bouchon Bakery and is used to make delicious Cupid Cakes.
In the bowl of an electric mixer, combine egg whites and sugar. Set bowl over (but not touching) simmering water, and whisk until sugar has dissolved. Place bowl on mixer, and continue whisking using the whisk attachment until smooth and fluffy; fold in vanilla seeds to combine. Keep refrigerated until ready to use.