Preheat the oven to 350°F (175°C) and line a baking sheet with parchment paper.
In a medium bowl, combine the sugar, melted butter, cinnamon, salt, and vanilla extract.
Add the pecans to the bowl and stir until they are well coated with the sugar mixture.
Spread the pecans in an even layer on the prepared baking sheet.
Bake in the preheated oven for 20-25 minutes, stirring halfway through, until the pecans are golden brown and caramelized.
Allow the pecans to cool completely on the baking sheet. They will become more crunchy as they cool.
Serve the candied pecans as a snack or use them as a topping for salads and desserts. Store any leftovers in an airtight container.