In a small bowl, combine brown sugar, water, vanilla extract, and kosher salt. Stir until sugar dissolves and forms a syrup.

In a medium-large saucepan, heat over medium heat, adding pecan halves. Toast for 2-3 minutes, stirring frequently, until fragrant.

Reduce heat to low and drizzle the sugar mixture into the pan with the toasted pecans. Stir for 15 seconds to coat.

Spread coated pecans onto parchment paper in a single layer. Allow to cool for 10-15 minutes.

Transfer cooled pecans to an airtight container. They can be stored for up to two weeks.