In a large bowl, add the egg whites and vanilla. Use an electric mixer to beat the egg whites until bubbly and frothy.
Add in the 6 cups nuts and stir to coat with the sugars.
Spray your slow cooker with cooking oil to coat.
Add egg white-coated nuts to the basin of your slow cooker and add 1 cup of brown sugar, 1 cup of sugar, 2 Tbsp cinnamon, and ½ tsp salt. Mix together to coat thoroughly.
Cook on low for 3-4 hours, stirring every 20-30 minutes to prevent burning. When down to the last hour, add the ⅛ cup of water and proceed as usual, stirring to coat every 20-30 minutes.
Line a baking sheet with parchment or wax paper and spread the nuts out to cool. They'll be sticky so make sure to spread them out so they're not touching, unless you prefer nut clusters.