Prepare a 9×13 baking pan by lining it with parchment paper.
In a large saucepan or pot over medium heat, combine the mini white marshmallows and unsalted butter. Continuously stir the mixture as it heats up.
Once melted, remove from heat and stir in the vanilla extract.
Fold in the Rice Krispies and mini eggs until well coated.
Pour the mixture into the lined baking pan and spread it evenly, pressing gently.
Leave to set for an hour, then remove and cut into squares.
Best if served fresh but can be stored in an airtight container for up to three days.
