Preheat the oven to 250° F. Pour mini pretzels into a large bowl and set aside.

In a medium saucepan, melt butter, brown sugar and corn syrup. Once melted, stir continuously until sugar dissolves and the mixture begins to boil. Let it boil for about 3-4 minutes without stirring. It should turn into a caramel-like toffee sauce.

Remove the toffee sauce from heat and stir in the baking soda and vanilla extract.

Quickly pour the toffee sauce over the pretzels on the baking sheet. Use a spatula to spread it evenly, making sure all pretzels are coated. Pour half of the toffee bits over the pretzels and stir together to coat evenly.

Evenly spread the pretzels into the baking pan. Bake for 60 minutes, stirring every 15 minutes.

Once the pretzels are done baking, remove from the oven and sprinkle the remaining toffee bits over the pretzels immediately.

Once the toffee has hardened, break the pretzels into pieces and enjoy your delicious Toffee Pretzels!