01 - Line a large rimmed baking sheet with parchment paper. Spread the mini pretzel twists in a single even layer across the entire surface.
02 - In a small saucepan set over medium heat, combine the butter, brown sugar, corn syrup, and sea salt. Stir constantly with a heatproof spatula until the butter melts and the mixture reaches a gentle boil.
03 - Continue boiling for 2 to 3 minutes, stirring frequently, until the toffee thickens slightly and turns a deep golden amber color. Remove from heat and immediately stir in the vanilla extract.
04 - Pour the hot toffee evenly over the pretzel layer. Use a spatula to gently toss and fold the pretzels, ensuring each twist gets thoroughly coated in the toffee mixture.
05 - Let the coated pretzels rest at room temperature for about 10 minutes so the toffee firms up and adheres to the pretzels.
06 - Place the chocolate chips and oil in a microwave-safe bowl. Heat in 20-second bursts, stirring between each interval, until the chocolate is completely smooth and glossy. Drizzle the melted chocolate over the toffee-coated pretzels. Finish with a light sprinkle of flaky sea salt if desired.
07 - Allow the pretzels to set completely until the chocolate hardens. Break apart any clusters and transfer to a serving bowl or storage container.