Line baking sheet with parchment paper and preheat oven to 400 degrees.
Lay an even layer of pretzel sticks across entire sheet, set aside.
Add butter, brown sugar, and salt to a small saucepan and bring to a boil. Continue boiling mixture for 4-5 minutes while stirring frequently. When mixture thickens and darkens remove from heat and stir in vanilla.
Pour mixture evenly over the pretzels and place baking sheet in the oven for 5 minutes.
While the first layer is baking, melt chocolate in the microwave in 30 second intervals, stirring each time until smooth.
Remove baking sheet from oven and let cool 1 minute, then pour melted chocolate evenly across the top. Add holiday sprinkles if desired.
Place in fridge (not freezer!) for 3-4 hours or overnight. Once cool, cut into squares and serve.