Preheat oven to 300 degrees and line two baking sheets with parchment paper.
Mix the sugars and cinnamon together in a bowl. Set aside.
In a very large bowl, combine the vanilla and egg whites with a whisk. Add the pecans and stir until they are all evenly coated.
Place the pecans and the dry mixture in a large gallon bag and shake until well coated.
Pour the pecans onto the baking sheets and spread evenly.
Bake for 60 minutes, tossing every 20 minutes.
Let cool to room temperature and store in an airtight container.
