In a large bowl, mix together the vanilla cake mix, eggs, water, and oil.
Divide the batter between two bowls
Mix a few drops of pink food coloring into one of the bowls.
Mix a few drops of yellow food coloring into the second bowl
Grease and flour a 7 inch bundt pan.
Pour half of the pink batter into the bundt cake pan
Drop scoops of the yellow cake batter into the pink batter
Pour remaining pink batter onto the yellow batter
Add 1 cup water to the inner bowl of the instant pot. Place trivet inside.
Make a foil sling and carefully lower filled bundt pan on top of trivet in the instant pot. Loosely fold foil sling over the top of the bundt pan.
Close lid and set to sealing.
Cook on high pressure for 35 minutes.
Quick pressure release.
Let cool on a cooling rack for 30-60 minutes.
Use a knife to gently separate the cake from the sides of the bundt pan and empty the cake onto a plate.