Line a baking sheet with parchment paper. Set aside.
In a medium microwave-safe bowl, melt white chocolate chips in 30-second intervals, stirring between each, until smooth and fully melted.
Stir peanut butter into the melted white chocolate until fully combined and smooth.
To a large mixing bowl, add crispy rice cereal. Pour the white chocolate and peanut butter mixture over the cereal and gently stir until the cereal is evenly coated.
Let the mixture cool for about 5 minutes. It should still be warm but not hot, so the marshmallows don't melt.
Fold in mini marshmallows.
Using a 2-tablespoon scoop or spoon, drop the mixture onto the prepared baking sheet. If needed, gently press or shape them into mounds.
Top each cookie with mini chocolate chips.
Let cookies set at room temperature for about 30 minutes, or refrigerate for 15 minutes until firm.