Preheat oven to 300ºF / 150ºC. Line a large baking sheet with a Silpat or parchment paper and set aside.
In a medium bowl, mix together sugars, cinnamon, and salt. Make sure to break up any brown sugar clumps, if you have them. Set aside.
In a large bowl, whisk the egg white and vanilla together until just frothy. Add the pecans and gently toss using a spatula or your hands, until the pecans are well coated. Add the sugar and cinnamon mixture and keep tossing until pecans are completely covered.
Spread the pecans out on prepared baking sheet in a single layer. Bake for about 40-45 minutes, stirring two or tree times. The sugar mixture will bubble up a bit but it won’t harden until the nuts are cool. Remove tray from the oven and if using Maldon salt, sprinkle some on now (about 1/4-1/2 teaspoon should do it). Let the pecans cool on the baking sheet. When completely cool, gently break apart any nuts that have stuck together and store in an airtight container. Nuts will keep for at least two weeks.