Combine the butter and peanut butter. In a large mixing bowl, use a handheld mixer or a sturdy rubber spatula to blend the creamy peanut butter and melted butter until smooth and well combined. The mixture should be creamy and thoroughly combined.
Add the cereal and powdered sugar. Gently stir the Rice Krispies cereal until evenly coated with the peanut butter mixture. Then, mix the powdered sugar until everything is well combined and forms a firm, cohesive mixture.
Shape and chill. Line a cookie sheet with parchment or wax paper. Using a tablespoon, scoop out portions of the peanut butter mixture. Then, lightly grease your hands and roll each portion into a ball about the size of a walnut. Next, place the balls onto the lined cookie sheet and refrigerate for at least 30 minutes or until firm.
Melt and dunk. In a microwave-safe bowl, melt the chocolate in 30-second intervals, stirring in between to prevent burning. Continue until the chocolate is completely smooth. Dip each peanut butter ball into the melted chocolate, ensuring it’s fully coated. Place the coated balls back onto the lined baking sheet.
Chill again. Chill the chocolate-covered peanut butter balls in the refrigerator for 15-20 minutes or until the chocolate has fully set. Once the chocolate is firm, they’re ready to enjoy!