Step 1: Prepare the Baking Dish - Begin by lining a 9x13 inch baking dish with parchment paper. This will make it easier to lift the bars out once they set, allowing for cleaner cuts.
Step 2: Crush the Pretzels - Take 3 cups of mini pretzel twists and crush them into small pieces. You can do this by placing them in a resealable bag and using a rolling pin or simply pulsing them in a food processor. Set aside the remaining 24 pretzels for topping.
Step 3: Mix the Base - In a large mixing bowl, combine the crushed pretzels, 1 cup of melted butter, 2 cups of creamy peanut butter, and 2 cups of powdered sugar. Using a spatula, mix until all the ingredients are well combined and form a thick, sticky base.
Step 4: Press the Mixture into the Dish - Transfer the mixture into the prepared baking dish. Press it down firmly and evenly to create a solid base. This will ensure that the bars hold their shape once cut.
Step 5: Prepare the Chocolate Topping - In a microwave-safe bowl, melt the 1 cup of semi-sweet chocolate chips in 30-second intervals, stirring in between until smooth. Be careful not to overheat the chocolate.
Step 6: Assemble the Bars - Pour the melted chocolate over the pretzel-peanut butter base, spreading it evenly with a spatula. Then, place the remaining whole pretzels on top for a decorative touch and added crunch.
Step 7: Chill and Set - Refrigerate the assembled bars for at least 2 hours, or until the chocolate is fully set. This step is crucial for achieving the perfect texture.
Step 8: Slice and Serve - Once set, lift the bars out of the baking dish using the parchment paper. Use a sharp knife to cut them into squares or rectangles. Serve immediately or store for later!