In a small bowl mix together sugar, cinnamon, and salt
In a separate medium-sized bowl whisk together the egg white and vanilla until frothy.
Mix the pecans into the egg froth and then add the sugar mixture. Toss until evenly coated.
Evenly spread the coated pecans over the baking sheet. Bake for 1 hour until they are even brown. Be sure to stir them every 15-20 minutes.