Crush the pretzels in a zip-top bag using a rolling pin until you have a coarse crumb, about 1-2 minutes.

In a medium bowl, mix the crushed pretzels with ½ cup melted unsalted butter and ¼ cup brown sugar until well combined and sticky.

Line an 8x8-inch baking dish with parchment paper and pour the pretzel mixture into the dish, pressing it down firmly.

Drizzle the salted caramel sauce evenly over the pressed pretzel base and use a spatula to spread it.

Place the prepared dish in the refrigerator and chill for at least 1 hour, or until the caramel is firm.

If desired, melt ½ cup of chocolate chips and drizzle over the top once the bars have chilled.

After the chocolate has set, use a sharp knife to cut the bars into squares or rectangles.