For the peanut butter pretzel layer:
• ¾ cup (170 grams) unsalted butter, melted
• 1 and ½ cups (180 grams) powdered sugar
• 1 cup (250 grams) creamy peanut butter
• 2 cups (200 grams) crushed pretzels (measured after crushing)
For the topping:
• 1 (12-ounce) package semi-sweet chocolate chips
• ¼ cup (65 grams) creamy peanut butter
To make the peanut butter pretzel layer:
1) Line a 9×13 inch baking pan with aluminum foil or parchment, making sure to leave some overhang for easy removal, and set aside.
2) Add the melted butter, powdered sugar, peanut butter, and crushed pretzels to a large mixing bowl and mix until fully combined. Scoop the mixture into the prepared baking pan and press it down into one even layer.
To make the topping:
1) Add the chocolate chips and peanut butter to a microwave safe bowl and microwave in 20-30 second increments, stirring well after each increment, until melted and smooth. Pour the mixture on top of the bars and spread it around into one even layer.
2) Cover tightly and refrigerate for at least 1 hour, then remove from the pan, and slice into bars.