In a small saucepan over medium heat, melt the butter and whisk in the brown sugar and peanut butter. Heat until sugar dissolves, then remove from heat and let cool.

In a large mixing bowl, beat cream cheese with powdered sugar until creamy. Add the cooled brown sugar mixture and mix until combined.

Fold in mini chocolate chips and chopped Reese's peanut butter cups. Serve immediately or refrigerate until ready to serve. Enjoy with pretzels, animal crackers, or graham sticks.