Preheat oven to 250 degrees F. Grease a large baking sheet. (Do NOT use parchment paper or foil. Bake directly on the greased pan).
In a small bowl, combine sugar, sea salt, and cinnamon, set aside.
In a large mixing bowl, whip egg white and vanilla with a whisk until frothy (about 1 minute).
Add almonds to wet mixture and stir until evenly coated.
Once almonds are coated, sprinkle the dry ingredients over the almonds and stir until evenly distributed. Make sure to scrape any extra cinnamon sugar mixture off the sides and bottom of the bowl and incorporate it into the almonds.
Spread the almonds evenly, in a single layer, on the prepared baking sheet.
Bake at 250 degrees F for 1 hour. Stir every 15 minutes. Even if they look done after 45 minutes trust me and bake for the full hour.
After one hour remove the almonds from the oven, give them a final stir and let them cool on the baking sheet or enjoy them warm!
Store in an airtight container at room temperature or in the freezer!
