Prepare the Baking Sheet:
Preheat oven to 350°F (175°C). Line a baking sheet with parchment paper or a silicone mat.

Toast the Pecans:
Spread pecans in a single layer and toast for 8–10 minutes, stirring halfway, until fragrant and golden. Cool slightly.

Make the Caramel Mixture:
Melt butter over medium heat. Stir in brown sugar and bring to a gentle boil. Let boil for 2–3 minutes without stirring. Remove from heat and stir in vanilla and sea salt.

Coat the Pecans:
Toss toasted pecans with caramel mixture until evenly coated.

Bake the Bark:
Spread coated pecans back on the baking sheet. Bake for 15–20 minutes, stirring every 5 minutes, until caramel is bubbly and pecans are glossy.

Cool and Break:
Cool for 10 minutes, then break into clusters while still warm. Let cool completely.

Store:
Store in an airtight container at room temperature for up to 2 weeks.