Start by lining a muffin tin with parchment paper liners.
In a mixing bowl, combine salted creamy peanut butter, unsalted butter, light brown sugar, and powdered sugar. Mix until smooth and creamy.
In a microwave-safe bowl, add chopped dark or milk chocolate. Heat in the microwave in 30-second intervals, stirring until fully melted.
Spoon a layer of melted chocolate into the bottom of each muffin liner, enough to cover the base.
Add a generous scoop of the peanut butter filling on top of the chocolate layer.
Pour more melted chocolate over the peanut butter filling, ensuring it's completely covered.
Place the muffin tin in the refrigerator and let the cups chill for about 30 minutes, or until the chocolate is firm.
Once set, remove the peanut butter cups from the muffin tin, peel off the liners, and enjoy!
