​indigestible food dyes for gender reveal parties.

The cakes will be purple.

Made from either a digestible pink dye with an indigestible blue dye,

Or a digestible blue dye with an indigestible pink dye.

That way the gender is revealed the next day to all the party-goers.

They can post pictures revealing the baby’s gender on the parents social media to celebrate.

First poster wins a prize.