Preheat oven to 250 degrees F
Mix sugar, cinnamon, and salt together in a bowl.
Whisk egg white in a separate bowl until frothy. Toss pecans in the egg white mixture. Mix sugar mixture into pecan mixture until pecans are evenly coated. Spread coated pecans onto a baking sheet.
Bake in the preheated oven, stirring every 15 minutes, until pecans are evenly browned, about 1 hour.