01 - Line a large baking sheet with parchment paper and spread the mini pretzels in an even layer.
02 - In a small saucepan over medium heat, melt together the butter, brown sugar, corn syrup, and salt. Stir constantly until the mixture comes to a gentle boil.
03 - Continue to boil for 2–3 minutes, stirring frequently, until the mixture thickens and turns golden. Remove from heat and stir in vanilla extract.
04 - Immediately pour the hot toffee evenly over the pretzels. Use a spatula to gently toss and coat as many pretzels as possible.
05 - Let cool for 10 minutes to allow the toffee to set.
06 - For optional chocolate drizzle: Melt the chocolate chips and coconut oil together in a microwave-safe bowl in 20-second bursts, stirring in between, until smooth.
07 - Drizzle the chocolate over the toffee-coated pretzels and sprinkle with sea salt flakes if desired. Let the pretzels set completely before breaking apart and serving.