Line an 8x8-inch pan with parchment paper.

Remove the cream filling from 2 Oreo cookies and crush the cookies into fine crumbs. Chop the remaining Oreos, reserving about 2 tablespoons for topping.

In a large bowl, combine the rice cereal, the chopped Oreos, and a small handful of marshmallows.

Melt the butter over low heat. Add the remaining marshmallows and stir until completely melted and glossy. Stir in the vanilla bean paste, crushed Oreo crumbs, and salt until evenly combined.

Pour the marshmallow mixture over the cereal mixture and gently fold everything together until evenly coated.

Transfer the mixture to the prepared pan and lightly press it into an even layer. Sprinkle the reserved chopped Oreos over the top and gently press them in.

Let the treats set for 1 to 2 hours before slicing and serving.