- Preheat oven to 350°F (175°C) and line a baking sheet with parchment.
- Spread pretzels in an even layer on the baking sheet.
- Melt butter and brown sugar in a saucepan over medium heat, stirring until it boils.
- Let it boil 3 minutes without stirring.
- Remove from heat and stir in vanilla and baking soda (it will foam).
- Immediately pour caramel over the pretzels and toss to coat.
- Bake 10 minutes until bubbly.
- Remove from oven, sprinkle toffee bits on top, and lightly press them in.
- Let cool completely, break apart, and enjoy.
