Start by melting the unsalted butter and creamy peanut butter together in a saucepan over medium heat. Stir until the mixture is smooth and well combined.

Once melted, remove the pan from the heat. Stir in the butterscotch chips and the vanilla extract until they’re fully incorporated.

Gently fold in the fruity mini marshmallows, ensuring they’re evenly distributed without being crushed.

Pour the mixture into a greased square pan and spread it out evenly.

Let the squares cool and set completely before cutting them into bite-sized pieces. Enjoy your nostalgic treat!