Line a baking sheet with parchment paper and set aside.
In a saucepan, melt the butter over medium heat. Once the butter has melted, gradually stir in the granulated erythritol. Cook for 8-10 minutes stirring occasionally.
Remove from heat and stir in the vanilla and pecans. Transfer the mixture to the baking sheet and use a rubber spatula to spread the mixture in an even layer
Let cool at room temperature and then transfer to the refrigerator for 1 hour before cutting into pieces and serving.