Start by lining your 9x9-inch baking pan with parchment paper, leaving some overhang on the sides for easy removal later.
In a mixing bowl, combine the creamy peanut butter, melted butter, vanilla extract, and powdered sugar. Mix until well-combined.
Transfer the peanut butter mixture to the prepared baking pan and spread it evenly across the bottom.
In a microwave-safe bowl, melt the chocolate Candiquik or Almond Bark according to the package instructions, stirring every 30 seconds until smooth.
Pour the melted chocolate over the peanut butter layer in the baking pan and spread it evenly.
Sprinkle the finely chopped peanuts evenly over the top before the chocolate sets.
Place the baking pan in the refrigerator and let the bars chill for at least 2 hours or until the chocolate is fully set.
Once the chocolate is firm, lift the bars out of the pan using the parchment paper overhang and cut them into squares.