First, preheat your oven to 225℉ (107℃). Next, measure and pour the pecans into a large, wide mixing bowl. In a separate smaller bowl mix the sugars, salt, and cinnamon. Then, set the sugar mixture aside until you need it.
In a third bowl, whip the egg white with the vanilla until it’s foamy. Pour the egg mixture over the pecans and use a spatula or large spoon to fold the pecans until they are completely wet.
Next, pour the cinnamon-sugar mixture onto the pecans and stir again until the mixture becomes sandy and sticky and fully coats the pecans.
Now that the pecans are ready, pour them onto a lined (parchment papeer or silicone) baking sheet and try to spread them into a single layer as much as possible. Bake them in the oven for 1 hour. While they are roasting, turn and shift the candied pecans every 15 minutes. They will dry out and crisp as they roast.
To check that the pecans are cooked all the way through, take a bite out of a few nuts. They should feel the same texture all the way through and the cross section should look uniform. (If they aren't done, there will be a thin line of uncooked nut in the very center.) When done, remove the nuts from the oven and let them cool for 5-10 minutes before eating.