Line a baking sheet with parchment paper and set aside.

Toast the pecan halves in a dry skillet over medium heat for about 5 minutes, stirring occasionally until fragrant.

In a heavy-bottomed saucepan over medium heat, combine the granulated sugar, unsalted butter, light corn syrup, and vanilla extract, stirring until the sugar dissolves, about 2-3 minutes.

Increase the heat to medium-high and bring the mixture to a rolling boil.

Continue cooking, stirring constantly, for 5-7 minutes until the mixture turns a golden amber color.

Stir in the toasted pecans and mix until fully coated, about 1 minute.

Quickly pour the mixture onto the prepared baking sheet and spread it out evenly with a spatula to about 1/4-inch thickness.

Allow the candy to cool completely at room temperature, about 30 minutes, then break into pieces for serving.