Start by placing the room-temperature salted butter and creamy peanut butter into a mixing bowl. Using a spatula or an electric mixer, cream the two together until they are well combined and smooth.
Next, add the vanilla extract to the butter and peanut butter mixture. Gradually incorporate the confectioners sugar, starting with 2 1/2 cups. Mix until everything is well blended. If the mixture is too soft, feel free to add more confectioners sugar until you reach your desired consistency.
Line your 9x9 inch baking pan with parchment paper, leaving some overhang for easy removal later. Spread the peanut butter mixture evenly across the bottom of the pan, using your spatula to ensure it's packed down firmly.
Take your pretzel twists and crush them slightly. You can do this by placing them in a zip-top bag and using a rolling pin to gently break them into smaller pieces. Sprinkle the crushed pretzels evenly over the peanut butter layer, pressing them down lightly to ensure they adhere.
In a double boiler or a microwave-safe bowl, melt the chopped chocolate until it’s smooth and glossy. If using the microwave, heat in 30-second intervals, stirring in between to avoid burning.
Pour the melted chocolate over the peanut butter and pretzel layers in the baking pan. Use your spatula to spread it evenly across the top.
Refrigerate the bars for at least 1-2 hours or until the chocolate has fully set. Once firm, lift the bars out of the pan using the parchment overhang and cut them into squares or rectangles.
