Preheat your oven to 350°F (175°C).
Line a large baking sheet with parchment paper.
Spread the mini pretzels evenly on the prepared baking sheet.
In a medium saucepan, melt the salted butter over medium heat. Add the light brown sugar and stir until it comes to a boil. Boil for 3-4 minutes.
Pour the hot caramel mixture over the pretzels, ensuring all are coated.
Bake the pretzel and caramel layer for 5-7 minutes, or until bubbly.
Remove from oven and sprinkle the white chocolate chips over the hot caramel layer. Spread melted chocolate evenly.
While warm, sprinkle rainbow sprinkles over the top.
Melt dark chocolate and drizzle over the bark.
Let the Pretzel Bark Candy cool at room temperature for 1-2 hours or refrigerate for 30 minutes.
Once set, break into pieces and serve.