Preheat your oven to 400°F (200°C). Prepare a baking sheet by lining it with parchment paper to prevent sticking.
Arrange the mini pretzels in a single, even layer on the parchment-lined baking sheet, ensuring they do not overlap.
In a medium saucepan, melt the butter over medium heat. Once fully melted, add the packed brown sugar to the saucepan. Stir the mixture continuously until it becomes smooth and starts to bubble, which should take approximately 3-4 minutes.
Once bubbly, carefully pour the rich toffee mixture evenly over the pretzels, making sure each pretzel is well-coated. If necessary, use a spatula to help distribute the toffee mixture evenly across the pretzels.
Place the baking sheet in the preheated oven and bake the pretzels for 5-6 minutes, removing them once they are bubbly and golden.
Take the pretzels out of the oven and promptly sprinkle the chocolate chips over the top. Allow them to sit undisturbed for about a minute to soften the chocolate, then use a spatula to evenly spread the melted chocolate across the pretzels.
While the chocolate is still warm and pliable, sprinkle the chopped nuts generously over the chocolate layer, followed by a delicate dusting of sea salt for a balanced flavor enhancement.
Allow the pretzels to cool completely at room temperature. For a quicker cooling option, you can place the baking sheet in the refrigerator for about 30 minutes. Once cooled, break the pretzels into pieces to serve.
Notes
Serve in a decorative bowl with warm melted chocolate for dipping.