Directions:

1. Prepare the base:** Preheat the oven to 350°F (175°C). In a bowl, mix crushed pretzels, melted butter, and granulated sugar. Press the mixture firmly into a greased 9×9-inch baking pan. Bake for 8-10 minutes, then let cool.
2. Make the caramel layer:** In a saucepan, combine brown sugar, butter, and heavy cream over medium heat. Stir constantly until the mixture begins to boil. Cook for 4-5 minutes until thickened. Remove from heat and stir in vanilla extract. Pour the caramel evenly over the cooled pretzel crust. Chill in the refrigerator for 30 minutes.
3. Add the chocolate topping:** Melt the semi-sweet chocolate chips in a microwave-safe bowl, heating in 30-second intervals and stirring until smooth. Spread the melted chocolate over the caramel layer. If using white chocolate, drizzle over the top for decoration.
4. Chill for at least 1 hour, or until set. Slice into bars and enjoy the crunch!