Why is my dough so sticky before chilling?

This dough is intentionally soft due to the sour cream and the creamed butter; chilling for at least 30 minutes firms the dough so it’s easier to roll and marble without losing shape.

Can I swap candy eyeballs for the white chocolate chips?

Yes — press candy eyeballs onto the shaped cookies right before baking so they sit on top and don’t sink into the dough; they’re a fun Halloween swap.